I remember when traveling across country a few years ago, I stopped in a gym in Oregon next to the motel I was staying at and paid the daily fee. When I went to the locker room to get changed I noticed this guy sitting at a bench facing the shower with only a towel over his lap, reading a newspaper and looking up every few seconds to see what was going on in the shower. I came back 45 minutes or so later and the same guy was STILL in there reading the paper and checking out all the dudes in the shower. I think it was like a daily routine or something. So creepy.
The desk attendants at my gym have to do, what they call, "Random cock checks." Walk in every 5-10min, using different membership employees, the attendants or whoever...to check on the showers to make sure there aren't two (or more, as has been found before) dudes going at it in the the steam room, sauna or shower.
And a friend of mine talks about how guys will wait in the shower for an hour or more so they can make an advance on some guy they like if he comes to wash himself. As he says "Right now, there is a man in the showers with the worlds cleanest genitals just waiting for another man to come in so they can fuck."