The Equipment Hog
You have one body. Therefore, you should only take up one piece of equipment at any given time. "Claiming" multiple machines or benches in the name of your superset is fine if you're the only person at the gym, but it's straight-up unacceptable if other people are waiting.
Same thing goes for hoarding equipment -- rounding up three sets of dumbbells, two medicine balls, a BOSU ball, a bench, a barbell, and a squat rack all at the same time is both rude and a slippery slope on the path to one day owning 1,000 cats.