Eh, there's also a good portion that take every opportunity to tell you just how pathetic WCBB is, which stems from god knows what.
To do a little psychology - I think it stems from many supporters of women's basketball believing, and vocally presenting their beliefs, that women's basketball is something it is not.
Examples include - "fundamentally sound." "played the right way." and my personal favorite: "could beat some men's teams."
I think the last one is the one that sets people off the most. I remember back in the Rebecca Lobo era when my good friend first discovered sports and told me that, "the women's team could play the men's team close." I responded with, "if the men's team played that game seriously, the woman's team would have trouble scoring 10 points." He got all angry and defensive. Meanwhile, I had played thousands of hours of basketball and he was, essentially, a non-athlete.
Doesn't really bother me - I like the top of the woman's game. I find it fun to watch the top teams playing. I like the rivalries. Thought the nappy headed hoes at Rutgers thing was awesome. Tennessee/UConn is fun. Notre Dame's rise is interesting. But I don't get bothered when the fans oversell the product. That's fine with me. It's their thing, and it's good they're proud of it.
I can see, however, that it really chafes some hardcore bball fans when they do things like compare mbb and wbb all time records. The only thing the two sports have in common are the equipment and the rules.
So I think that's why people go out of their way to knock it - they're not being nasty for the sake of nasty, they're trying to, inelegantly, inform the wbb fans that they are not the same as mbb.