Do people really ask others to stop using a machine so they can use it themselves, like they are too impatient to wait their turn? Sounds a bit rude, calling it chummy or not.
I wouldn't know anything about gym etiquette though, if there is any.
A chum would be a friend here I think, but it's kind of an old word for it.
They never do, or at least never in my experience. I have had people asking if they can work in with me before though which pretty much means sharing because they cant be bothered waiting. Its horrible. I don't go to socialise and I certainly don't go to chum folk!
It is quite old fashioned isn't it!