The difference being that with iMessage people can trigger the bug remotely and there's little you can do about it except turn it off completely (as someone I know did end up doing). Hey, I didn't say that what they were doing was a good idea :)
No wait, I was describing a sane world, but this is a world where we decided to fund everything with advertising ("This drug rehabilitation clinic sponsored by OxyContin") and so actually you can do exactly that.