Well, in my experience there's a very wide range of motivations and reasons for girls to hook up with a middleman business partner (aka pimp).
What does seem to be very common, though, is that it is almost always very young girls (often times TOO young girls) who are the ones most likely to choose pimped meat status over being an indy. In fact, it seems to be a standard MO for pimps like Carrot Top/Lakers_fan/Enough_Alreadya/AGL to recruit young, down-on-their-luck girls, such as Jazzy, Erin and now, it seems, Kelsey, to their stables.
What you don't see very often are older, experienced providers who have always been indy who, all of a sudden, decide that it's a wise business move to choose up with some cheese-dick pimp or another. It seems that gullibility and poor judgement are, in large part, a function of age. It's the same thing with tobacco use: hook'em early or miss your chance.
Additionally, many of these young girls not only come from financially impoverished backgrounds, but from emotionally impoverished ones as well, where they've been subjected to abuse, neglect and abandonment. A childhood such as that leaves them vulnerable to the manipulations of pimps who seem to have developed a very fine sense of intuition with respect to whom might be most amenable to their overtures and attention, based on these girls' neediness. Once inside their heads and hearts, it's just not that hard for pimps to gradually take over the lives of these young girls and then proceed on to the usual course of abuse, coercion and cynical manipulation that most of us here find so reprehensible.
Personally, I don't know a single girl who is now indy or retired that started out in the biz as pimped meat who thinks that that was a wise move or who materially benefited over the long term by having such a business association.
In this day and age, any girl with a smart phone (or just reliable access to one), a free RB membership and bus fare can be in business for herself. Pimps traditionally provided physical protection for their girls, front money for pro pics and decent clothes, transportation, food, a black book of eager customers, etc. In exchange, his girls do ALL the work, take most of the risk (of arrest, disease, etc.) and turn over ALL their earnings to "daddy".
Sound like a fucked deal to you? You fuckin' A it is!