How can you possibly know that? This is a site with a very vocal minority where BB disapproval is concerned but don't let that fool you into thinking it's the norm. No-one can know without a cast iron honest survey of who does what to who - and you ain't getting that anytime soon.
Most SPs on AW don't have BB listed in their likes list. They also explicitly state in their Q&A section that they don't do BB. Others will say that if you've been with someone who does BB in your feedback list then they won't see you.
Plus, looking at it from a purely selfish point, it still doesn't make sense. The risk of getting infected isn't worth it because:
1. If she has something visible and the punter sees, he's gonna be a bit disgusted and put off and not return.
2. If she has something that's not visible, the punter will realise after a few days/weeks who he got it from and he won't return.
3. If she doesn't have something, she might catch something from a punter, leading to 1 or 2.q
Even if a punter doesn't actually care about the disease, their wife certainly will when they see it.
So a BBers customers are literally limited to single guys who don't care about diseases.
Plus, I don't think (Banned site removed) is as active as UKP? I think both sites provide a good comparison of the amount of BB and non-BB punters.