i think you answered your own question
i don't think it means she wants to date you outside of work... although it does happen.
As in 'I really genuinely enjoyed getting paid to fuck you, let's go against all my instincts.'
Duh. Yes it happens but probably not like that. Most of the women I've shagged for free who are whores did not start off by taking money. The punter-wg relationship is too easily set deep. In a couple of cases I knew they worked but just enjoyed their company for the banter and we decided to shag each other's brains out. It would have been highly offensive to offer money.
Both times I have dated women that I have first paid to have sex with, the paid sex was shite, and the free sex awesome. But you can't exactly plan these things with any certainty and usually not at all.
Since there's wgs reading this, it's worth saying that an error some prossies make if they fancy a guy is to attempt a sliding scale with freebies and discounts. This doesnt work. She is reaffirming her whore status while thinking she can edge awayfrom it - bad news for both people. She sshould just come out and say it and see how he takes it IMO. Bear in mibd most men don't want a whore as a g/f they just like the fantasy.
To guys, if she doesn't say so in so many words just treat it the same as if your bank manager or some other overpaid service industry worker said they really like you. A compliment or gratuitous marketing, nothing more.