The moral flaw "the crowd" made was that it was men attempting to coerce sex from other men. Lot wanted to solve the problem by throwing his virgin daughters into the crowd.. which was apparently a perfectly righteous thing to do.
And anyways, that's why you shouldn't get your morality from an ancient book from a very different culture. Please don't throw any of your family members into crowds of rapists, it's not polite.
Let's not forget that hitting on someone is a continuum that ranges from flirtatious banter that you can enjoy with anyone to one's twisted idea of what hitting on someone entails that makes all their guests uncomfortable. Like asking "wanna fuck?"
Yes, hitting on someone in a way that makes them uncomfortable does make them uncomfortable and makes you a bad host. But I worry that you have an unhealthy understanding of flirting if you don't think it's something you or anyone can do without making someone else uncomfortable.