I don't know if you guys are still dating but that is precisely one of the things that bothers me, people ask you financial information as if it is nothing on the first five minutes of the interaction and then they get offended when you don't answer or evade the question
Sounds like those kind of people you are meeting are blatantly gold diggers. You're probably best off ending the interaction immediately or at least by the next morning if you're inclined to see what you can get from it.