Re: Tawnie Lynn (pictured)
What is wrong with specialist dating sites in principle?
What is wrong with mocking them, on principle?
Also, of course, people who pronounce themselves beautiful are opening the door for disparagement.1 And they're guilty of a category error, since while some aspects of physical attractiveness seem to be cross-cultural (e.g. facial symmetry), beauty is largely evaluated on subjective grounds that are highly culturally inflected. The pictures I found claiming to be of Lynn don't meet my standards, and I'd guess the same would be true of many of their members. There's no reason they should care about that, but having pronounced themselves beautiful according to some arbitrary metric, they have no defense against being evaluated, in public, against other such.
Now, as to whether she's shallow, stupid, etc, I cannot say; perhaps she's simply playing the role in order to take advantage of people who are shallow and stupid. In which case more power to her.
1I'm quite a looker myself. Disparage away!