It really depends on the individual. I won't go hang out with regional FA's on a layover unless I have gotten to know them a little beforehand, on that trip or a previous one. Otherwise you are asking for all manner of troubles. We had a captain who innocently bought some beers for an FA, and then got cited by the local vice because she was under 21. He got to enjoy the right seat for 6 months for that

Also, when it looks like the crew wants to go out to eat together I state up front that I want to eat at a real restaruant....otherwise you end up reaching a lowest-common-denominator consesus and eating at Arbys