I think a dvd with trailers or ads should just be in the dvd/blu ray extras and not forced on the audience or viewer.
Nobody really gives a fuck about the FBI warning it's not threatning or scarying anyone it's just there. It does seem like it is put out there just to annoy. It is petty and annoying but I could see it getting to the point of people just saying fuck the FBI and burning movies on the sole purpose of their annoying WARNING. I like how the mockery made of it on the Fight Club dvd.