I agree partly. Any crew member who is out partying every night until the small hours and then complains to crewing about fatigue, well, that is not on.
However, we all whinge when we are tired, that doesn't mean we are not fit to fly.
But when away, as you say, who wants to sit watching the 4 walls of their hotel room? Personally I feel a need to unwind with the rest of the crew, as I feel that socialising and having a good meal, maybe a few drinks, actually helps me to relax, gets rid of stress, and helps me sleep better, thus reducing tiredness. But it depends on just what the duties are like. If you get to your hotel and you have 11 hours until official report at the airport, that usually means you actually have about 10 hours at the hotel. As you say, you need to unwind and you need to eat, and before that you need to shower and change, so you go and do that and now you only have 6 hours before report. So yes, you are going to be tired. Of course, you could go straight to your hotel room, eat straight away from room service and immediately go to bed, but if it were me, I couldn't do that as I just wouldn't sleep. So I go and socialise with the rest of the crew.
Most crew members are fairly sociable, and many a crew go on about having a good night, that is a bit different from staying out clubbing for many hours, which I wouldn't do.
But if on min rest every night, its difficult not to get tired.