I usually go in the early mornings, when it's only the regulars and we all kinda know each other and know the common gym courtesies. However, I made the mistake of going on Christmas eve around midday, and it was packed with guys who were so incredibly discourteous and too self-involved to even notice how rude they were being. For example:
(1) There were four adjustable benches available for use, and three were in constant use. The fourth was taken up by the towel of this middle-aged guy who was clearly trying to do a circuit that was taking him all over the gym... and far away from the bench that he was using maybe once every ten minutes.
(2) There was another middle-aged guy who plopped his crap down in front of one of the two adjustable cable machines and used it once every 8 minutes or so. The rest of his time was spent hanging out on the only dip bars in the entire gym, browsing on his phone.
(3) There was one guy who was taking up two of the three squat racks. One of the racks he was using for deadlifts, which obviously do not require a squat rack at all. He was doing all this while also doing a circuit with other equipment.
Moral of the story: if they gym's crowded, I don't give a fuck what kind of circuit you want to do. Let others use the equipment and don't be a fucking hog. I just about lost it on all of them.