I have spent lots of time in hostels across the USA. I prefer the male dorms over the co-ed ones. I enjoy sleeping nude and know I have inadvertently put on a show while sleeping when I've kicked off the covers. If I do stroke in the male dorm, I try to be discreet, even though, I'm pretty sure everyone knows what I'm up too. I've walked in on or woken up to other guys beating off, some were being discreet and some were not. What I like about those experiences, is not the act itself (which frankly I find a little boring to watch), but the acknowledgement of participating in the act. That shared experience is intimate and makes me feel connected to my travel brothers.
Currently, I pretty much live in a hostel by hosting travelers through Airbnb. Since I'm the host, I don't sleep in the communal room, but I do share a bathroom with a gang shower. I'm always glad to see a guest toss off through the glass door or window that connects to my bedroom from the shower room. I have also had guests spy on me and I have carried on without acknowledging them or changing my focus. I'm also pretty sure guys have watched me without me even knowing.