Embedding Remote Buttons

So, aware web users and webmasters/webdevs know that by embedding remote images or even any file you essentially set up your page to direct visitors to other servers as well, sending along a lot of information. With big services like Google and Facebook this opens a lot of data mining possibilities for them. Facebook and Google with their Like and +1 Buttons can track visitors across websites. Track visitors browsers, OS, etc. And if the visitor has an account, can associate all the data to an account. Which websites did the user visit? When did he? Etc. And all that with visitors not even clicking the Like/+1 Buttons.

Some weeks ago heise.de published an anonymous version of a Facebook Like button, which would use a locally hosted image and only if you would want to click it it would load remote content. Facebook threatened them. After all, they were using Facebooks image. Now they still have an anonymous Like button with an altered image so anonymity and privacy is not dropped.

Google with their +1 Buttons states in their +1 button policy:

Publishers may not alter or obfuscate the +1 Button

So we have the same problem there … Now, how much would you have to alter the image so it is no longer trademarked? (if it is at all) And would hosting it locally fall under fair use? Would altering it slightly, so much you can tell the difference, be enough for it to fall under fair use? Greying it out maybe?