One of the sites allows a banner purchase at the front of each advertising section.... practically a representative of all of the girls on the section. I ran into that banner girl at a soiree and disagreed totally with her conduct. (Now I read here she's got terrible review and she's changed the spelling of her name!) When the site came to me to ask for advertising $$ I confronted them with their policy.  Same response.  "We just provide advertising and we sold the banner on a first come, first served basis. And she made it to the same party you did!!"
It's all about the almighty dollar.  Don't call girls from those sites and don't "hit" those sites when you surf.  We ask the sites how many hits they're getting when we shop who to advertise with.
XOXO Tara