"I never consented to Googles TOS, therefore it doesn't apply to me"
I must take exception to that statement.
I never consented to being born, but still feel I have a right to live
I never consented to be a citizen of my country (I was born here - no consent) yet the laws of the nation apply to me.
I never consented to war, famine, crime or a host of other things that nonetheless affect me and my life
I never signed anything regarding any of the above. I never took an oath until I joined the military, and later became an officer of the court.
On the flip side, for certain things consent IS necessary - if I don't consent to a squeegie bum to "wash" my windows, there is no obligation on my part to pay him, for example.
But, if I ask that squeegie bum to wash my window, then consent was made and the obligation exists.
Those are the two extremes. But what if I knowingly drive my car to a place where that squeegie bum is working, and allow him to clean the windows with the intention of taking advantage of those clean windows?
This creates an implied consent and therefore not paying is fraudulent and unethical. Implied consent also exists when you are born (you are assumed to consent to being born). There have actually been cases where people, unhappy with their lives, have sued their parents for creating them, saying there was no consent. The courts have always held that the advantages and opportunities afforded a living person override the drawbacks to such an extent that it would be irrational to withold consent, therefore consent is implied.
When you open a website to the public, that act of creation is considered consent to public visitors. If you don't want public visitors, then you must either not create a website, or you must lock it down with logins. People have argued that they posted their website but did not consent for anyone to visit (it was for personal use only) but they have always lost. Consent is implied through their actions and choices.
It would be the same as changing your clothes in the middle of a public park and then complaining about people "invading your privacy. By choosing that venue, your consent is implied. You can stand there yelling that you are not consenting until you are blue in the face, but your actions speak louder than your words, and it's unfair on the public to allow your words to control their behaviour at your whim. In this case, consent is not only implied, it is forced. This is an important concept. A persons mental vagaries, insanities and whims do not always control the concept of consent. Nor can you claim a lack of consent for the purpose of taking advantage of others. Consent applies to YOU, not others. It only affects others in relation to you, and then their own consent comes into play, as well.
Use of web technology implies consent to access from the web unless that consent if specifically denied.
Lets move on to search engines. Search engines automate public access via the web. They don't use back doors (without permission - you need to sign up for and consent to trusted feeds)
Therefore, as long as public access is used, a search engine visitor has implied consent to visit and index, unless that permission is deliberately withdrawn. Just like a human could visit and rank a bunch of sites, only faster.
But so far this only means that you have consented to SE's visiting and indexing, not to their TOS, right. After all, if I make a TOS that says that every site I visit is now owned by me, you are certainly not consenting to it just because I visit, there must be something more.
I suspect this is the crux of your arguement. Fine. Now that I've (hopefully) laid down the framework for consent, lack of consent, and implied consent, let's apply it to a search engine TOS, shall we?
We have established that you are NOT bound by the TOS of a visitor - they are bound by yours, though there are rules as to how much can be bound. For example, if you run a warez site and put in your TOS that law enforcement officers and their agents are not allowed in, don't expect that to make any difference at all - contracts don't override criminal law - they never have.
Ok, so a visit by Googlebot does not require you to suddenly comply with their TOS, anymore than a visit from me requires you to comply with my TOS.
So what good is a TOS? Well, it's when you use or visit a website that the TOS comes into play. If you use a search engine to generate ranking reports or do searches, then you are clearly using their site and therefore fall under their TOS for the duration of your visit.
So Googles TOS doesn't matter when they use you, but does when you use them.
So where does SEO fit? This is a more difficult area because when you do things to your site, you are not, at that time, bound by any TOS but your own, by definition. You can't spam yourself, because you have implied consent from yourself to do whatever you want (if that makes sense).
The only way Googles TOS would apply to a website other than itself would be if that site was using Google for something.
"Use" implies a positive force or decision. If you have a website but don't know what a search engine is and don't particularly care about traffic from it, then you are not "using" Google, anymore than you are "using" the squeegie guy in the above example. It's just something that is happening without your express or implied consent. There are several search engines that I've NEVER looked at or optimized for. I don't feel bound by their TOS in the slightest. I don't know what it is, and I don't care. Many of them are run by spammers and I have no intention of helping them in any way, or by being bound by their rules. They can include me or ban me as they wish, and it's not an ethical, moral, or legal issue for me to not care.
But, what if I deliberately did something to my site with the express intent of increasing my rankings for a particular search engine? At this point, I am "using" their engine, in that I am manipulating known controlling factors with the express intent of changing the traffic levels and rankings, then taking advantage of that traffic to my own benifit.
At this point, you are knowingly using and intending to be benifiting from the service, and therefore consent is implied. This implied consent is just as strong as your implied consent to be a citizen of your country, and therefore to be bound by it's laws. Try wiggling out of that one day (without leaving the country) and see how far you get. Implied consent is just as strong as overt consent, once the consent has been established ( the difference between "implied" and "overt" is in the "establishing" stage, not the "consent" stage)
There have, of course, always been people who claimed that they were not doing any such thing (like being an SEO and claiming that you don't care about your Google rankings, and therefore are not bound by it's TOS).
This is treated by looking at your actions, rather than your words. The courts have lots of experience with the "I didn't mean to do it" type of defences and look with some cynicism towards people going through the effort of knowlingly doing things that benifit them and then claiming that they didn't mean to benifit and it was all a "happy coincidence".
In short, an SEO is, automatically by his or her own actions and intents, bound by the TOS of the search engines they use and intend to benifit from. The process of SEO creates the implied consent to being bound to the TOS.
Search Engine Optimization (SEO) = an obligation to obey the TOS of the engines you are optimizing for and implied consent to the same.
"I never consented to Googles TOS, therefore it doesn't apply to me"