I love the bowel movement comment... it is very true, regularity is always important. BUT when we overnight, if it is long enough the entire crew usually goes out together. Of course, our entire crew is a grand total of 4 people, but hey, we're a crew. Most of our overnights are relatively short (under 12 hours) so no drinking is done. Even if it is close to 12 hours, nobody drinks, but we may go out to dinner. On a long layover of perhaps 15 hours we might have a drink and do some fun activity. When we flew to Charleston, SC and the overnight was long, crews would go to the beach. In Baton Rouge when the overnight is long some crews rent cars and go to New Orleans. I had a long overnight in Montreal last winter and even though it was freezing cold and sunny we went into the city and hung out for the day. But by no means do we revert to our wild college days and drink until we're so hungover the next day we swear off alcohol forever, but then proceed to do it all again that same night (nawww... never did that!!). We're professionals and when on overnights are technically working and when in the public eye, must remain composed and respectful. The hotel workers know exactly who we are when we're there, so the littlest thing can send nasty grams to headquarters.
I think at mainline carriers the attitude is a bit different. I think some of them separate the FAs and pilots, which I think is stupid. We're a crew from the moment we show at the airport to the moment we're off duty at the end of the trip. So we stick together, but once in awhile you have what we call, "slam clickers." These are people that go straight to their room and slam their door and next you hear the clicking of the locks. I personally like to hang out with my crew and enjoy getting to know my coworkers. Of course after a 7 leg day and being on duty 14 hours, all you really want to do when you get there is shower and sleep. This is usually the case and proves the regionals are on a different scale of glamor than the mainline carriers.