Having worked at a commercial gym, I can say with confidence that no one was getting paid to put the weights away. Some were there to check you in, others were there to train you or clean the shitter, and a few where doing administrative tasks. If you go to a smaller private gym, they usually have plenty of signs instructing you to put your own damn weights away. It's an assumed courtesy.
Because no one's getting paid to do it (and in fact, have another job that they have to do), when the gym gets busy and they have to do their job, people like you make working out a giant pain in the ass because you can never find the weights you need.
Put your fucking weights away like a big boy.