I'm not Obi Wan. Really.
I totally agree with you, and I have asked management over and over to make the (I believe minor) code changes that would allow Slashdot to display HTML5 videos.
I consider "render it how they like" the equivalent of freedom to choose your own clock face and size rather than the time the clock displays.
I'd been looking into this in a slightly different context. Recently, at Hacker Dojo, someone demonstrated an Android mod to me which dealt with applications that demand too many privileges. It has the usual "disable privileges" option, but for apps that won't run with privileges disabled, it sends fake info.
The demo showed generation of fake phone serial numbers and such. That's easy. Apps that improperly try to upload your address book, though, require generation of a plausible, but fake, address book. That's wasn't in the demo, but it's worth doing. Location data should probably be sent as a random walk from some random starting point.
If enough people do this, it will garbage marketing databases.
Advertising is the rattling of a stick inside a swill bucket. -- George Orwell