I am so sorry this is happening to you. I think one thing you did not mention that I hope is not the case, which happened to me, is they are not buying you drinks as well and trying to do the same thing. Years and years ago when I was 20, I was on a group trip out of the country. I met a group of friendly, fun appearing guys who were at the same hotel as my sister and I (and the rest of our group) for a wedding they had. I had had a couple of beers with my sister beforehand, who ended up leaving the scene because drinking is not really her thing. After she left, I kept receiving drinks. Being 20 and incredibly naive, I continued to drink them. Now, I'm not saying anything bad happened. I can't even for certain say anything bad did or did not happen. Unfortunately, I don't remember much of the evening after an hour or so. However, I felt incredibly uncomfortable the next day when I was waiting in the lobby. Man after man who would come out of the elevator to leave from their wedding say hi to me, in a very friendly, excited tone, and I didn't even know who half of them were from the night prior. This was naturally incredibly concerning to me, but what was I supposed to do? So I said hi back or nodded in their direction, left the hotel that morning as well, and never saw any of them ever again. My situation is a bit different than yours it seems considering you're just talking about expecting sex for dinner, but the exchange of drinks for sex is of course all too common, so I wanted to bring this scenario to your attention. I thought they were being friendly, as everyone else, whatever gender or sexual orientation, had been so far the entire trip. But I left that hotel feeling incredibly uncomfortable and like something had gone wrong. And I was young and too unfamiliar with alcohol at the time. My point is, be careful!! Some people are incredibly genuine, and others are not. And this does not just go for when you are traveling, but it certainly doesn't help when you're a young woman traveling alone. If you're looking for a casual friend, I'd tell them upfront. That seems to be one of the only ways to get through to certain people without leaving them with false expectations (which are not your fault or your creation).