I love the movie previews in cinemas. Nice to see trailers of what's coming out soon.
What I absolutely hate is adverts in cinemas, and the previews/non skip items on DVDs. To subject people to advertising like that when they have already paid is indefensible.
I started blocking ads when certain sites would bog down my browser with flash (namely, Entrepreneur.com). That's when I discovered ABP. It's just a nicer surfing experience for me without them. But then again, I'm the kind of person that thinks Nike is crazy if they expect me to pay for a t-shirt that simply says "Nike" on it (or carries their swoosh).
Just between you and me (I doubt anybody else is reading any more) I get annoyed at movie previews for the same reason...:) I think I'm the only one on the planet with that particular defective gene.