I've never been aware of much problem between the 2 disciplines. Both have a few egomaniacal ass muffins in them, but most of us respect each other. It takes a special kind of crazy to do either one at a high level.
A lot of powerlifters have crossed over to BB due to injury, myself included. I love BB. It is a different kind challenge, with the diet etc, but I'm glad I have an outlet for my need to lift and be competitive. If I could, though, I'd still be lifting HEAVY weight. It has always been my primary lifting obsession.
Now, if someone asks how much I bench press, I say "A lot" and quickly change the subject to the first pretty woman that walks by.