They probably are fully aware that nobody reads the clickwrap, that's an interesting point. It would be interesting to hear what a lawyer says about that. I don't think it's a truly reasonable defense and I wouldn't want to rely on it. (If we're thinking "ideal legal world", then I'd like clickwraps to be human-readable and people to actually read them.)

But I think there's a very clear distinction between a simple agreement with the original and with altering the DOM. If you are clever enough to alter the DOM you definitely know that the alterations are not going to be sent back to the server. You also know that agreeing will let you use the service because the server will think you agreed to the original. That seems like a clear-cut case of fraud to me. I don't see why an agreement to the original contract is invalidated because you weren't offered the opportunity to make a counter-offer (I agree that's a shitty situation, though). That's why I think it's like a contract in the mail; you get an offer and you can agree to that or not. You can make a counter-offer but it will be binned.

Consideration isn't solely concerned with monetary purchases, is it? I imagine they can construe your incoming data as valuable. It would be interesting to know if sites like Reddit can claim user interaction has inherent value for the site and for the users. I guess the EULA would be granting you license to use the software, but would not give any additional value to the developer so consideration does seem to invalidate that.

You're probably right that a ToS is going to be hard to uphold in civil court.

Anyway, thank you for elaborating, I'm glad to get a better understanding of your perspective and contract law.