I don't know if Google's motives are pure or not, but this is wrong: They are refusing to advertise CougarLife, a dating site for mature women looking for younger men. However, they accept sites for mature men seeking young women.
According to the New York Times, CougarLife.com was paying Google $US100,000 a month since October. The Mountain View company cancelled the contract saying that the dating site is "nonfamily safe".
Apparently, sites announcing "hot women", "Russian wives" and "young girls" are family safe, because those ads keep appearing in Google's network. In fact, the owners of CougarLife also own ArrangementSeekers.com, a site that puts together sugar daddies with young women. No problems from Google announcing that one.