Fruit bat, I'm sure that has a LOT to do with it.
The majority of pit type dogs simply aren't registered with any sort of a kennel club, so I think people don't realize just how popular they are. Sometimes people see AKC as the be all end all of dog registries, and just assume "oh, Labs are really the most popular dog in America," without thinking of every dog out there that ISN'T or CAN'T be registered by AKC.
Then add to your problem the fact that almost NO ONE out there can correctly identify an American Pit Bull Terrier, from a Staffordshire Bull Terrier, A Bull Terrier (Standard or Miniature), an American Staffordshire Bull Terrier, an American Bulldog, and any number of mixes out there that LOOK like they might be pitbulls, and the breed is REALLY in a heap of trouble.
And unfortunately, the minute aggression is involved, or someone gets bit by a dog, that person is probably a zillion times more likely to label said dog as being a pit bull- regardless of what the dog is. Someone mentioned earlier the news reports that talked about vicious pit bull attacks, with an accompanying photo of what was CLEARLY a purebred Labrador Retriever. I've seen those too. The general public is all too willing to jump on the band wagon of "pitbulls are dangerous," but they don't want to see "America's Favorite Dog" get dragged through the mud.
That's why these breed bans are so stupid. There just aren't that many people out there that can positively ID nearly ANY breed of dog, let alone be able to separate the breeds that all seem to have a vague resemblance to APBTs. I've seen grown men point at a BOXER and say, "oh look, there's one of those pit bulls."
HUH?
Proof positive that these breed specific bans are ABSOLUTE BS.