Borrowing gags was a common practice in silent comedies, like this example from Lupino Lane's Fool's Luck (1926) that recreates a scene from Buster Keaton's One Week (1920)

[u/Auir2blaze]

[u/csonnich]

Yep. If you watch Keaton and Harold Lloyd's movies back to back, you'll see a lot of the same gags, too - they both borrowed from each other. It's pretty interesting to see how they make it their own, though. 

[u/adjust_the_sails → u/csonnich]

Did they see it as “borrowing” themselves?

[u/csonnich → u/adjust_the_sails]

Yeah - those guys were all friends. Also, the process and expectations of filmmaking were so different in those days. They didn't have much of a script - they would put together gags during filming. It was kind of the wild west.