Kant 1. Doesn't ask "what's best for society"? It asks about the "universalizability principle" i.e. "if everyone acts like me is there a contradiction?". And in this case there is, if you browse an ad-supported site that could only exist if some people view the ads is a contradiction. You have to agree that some sites would shut down if everyone used adblock, and thus the principal stands. It's not about what's best for society if the sites shut down, just pointing out the ethical contradiction that if everyone acted like you, everyone couldn't act like you (at least not always on all sites).
Utilitarianism. You just have to measure the obvious units of good vs units of bad. Again, it's not like a math proof but you can identify the units of good vs units of bad. Can you provide an alternate counter proof that is more obviously correct than my analysis?
Social Contract: I'm talking about the implicit social contract that exist today. Page owners don't freely upload their page knowing that the web is pull and users will select the resources displayed. Many page owners aren't even aware of adblock, at least not all of them.
Basically what you've said is: Movie theater owners free open their doors knowing that the world is navigable and users will select whether they want to visit the pay booth or not. Movie theater owners do open their theaters with this in mind, but they don't intend for their users to skip the pay booth if they simply don't want to pay. That's not the social contract you take on when you visit a theater.
In this case, the social contract is stated in actually stated in words you can read. Just read the terms of service on many websites. They specifically say you can view the site if you don't block the ads: "you are not permitted to block the display of ads" -- http://www.livejournal.com/legal/tos.bml
Virtue Ethics: I think this one is pretty verifyable :) Just find someone that owns a ad supported site and tell them to their face that you use ad block and you think it would be shameful not to. See how you feel ;)