The condescension may be more prevalent around female contestants, but it's certainly not exclusive to them. My wife and I were watching an episode the other night, and there was a contestant from Cape Girardeau, Missouri. Bob spent several beats of an exchange trying to correct the contestant on where in the state it was located. And my wife just said, "Bob, what in the hell are you doing this for? He lives there!"
There was also a game in another episode where one of the small prizes was like a Crayola lap desk. And on it was a piece of paper that one of the models had written "Bob Barker <3 W.G.M.C.," which he of course to great pains to note and explain. Knowing what we know now, man, take me to the Silkwood shower.
Unrelated to that, having watched a couple plays of Trader Bob, it's bizarre how botched the order of the price reveals is in that game. Anyone who's paying attention is being told if the game's won or lost before the final reveal.