They don't like their jobs, they do it because the money is good. Those kids flipping burgers don't exactly like their jobs either :)
I had similar ideas to yours,then I had to do some work on prostitution and facts were convincing....
Starting point is usually existential problem, like with those who are flipping burgers, but they are usually coming from countries which are not allowing you even physical survival with that kind of job (150 euro per month?).
"Sexual trafficking includes coercing a migrant into a sexual act as a condition of allowing or arranging the migration. Sexual trafficking uses physical coercion, deception and bondage incurred through forced debt.
Trafficked women and children, for instance, are often promised work in the domestic or service industry
, but instead are usually taken to brothels where their passports and other identification papers are confiscated. They may be beaten or locked up and promised their freedom only after earning – through prostitution – their purchase price, as well as their travel and visa costs.
The main motive of a woman (in some cases an underage girl) to accept an offer from a trafficker is better financial opportunities for herself or her family. In many cases traffickers initially offer ‘legitimate’ work or the promise of an opportunity to study. The main types of work offered are in the catering and hotel industry, in bars and clubs, modeling contracts, or au pair work. Traffickers sometimes use offers of marriage, threats, intimidation and kidnapping as means of obtaining victims. In the majority of cases, the women end up in prostitution. Also some (migrating) prostitutes become victims of human trafficking. Some women know they will be working as prostitutes, but they have an inaccurate view of the circumstances and the conditions of the work in their country of destination."
it's from wiki, i don't have here those researches :S
After that, there is no way back.
In some countries situation is less problematic, so in a bigger percentage women who are doing that are in that just for money like you think, so you are right there...
unfortunately on global level, those women constitute a minority