what you're saying is freedom to create a signature graphic is only free if you don't offend someone?
I've got signatures turned off, so I don't see any of 'em. What we seem to be discussing here is bias.
Personally, Matt could delete the signature option and remove a lot of chatter and it wouldn't make me any difference either way. But, in my opinion, either allow anything that is not in the TOS, or allow nothing.