I didn't laugh, but I thought it was funny. I thought about how live audience reactions may have been a factor on the success of slapstick as a comedic element. The people who made this clip must have felt gratified when the audience laughed, and aspiring filmmakers of that era must have felt inspiration from watching the clip and noting audience reaction. I noted that I felt gratified when the younger guy gets wet after playing the trick on the older guy.
This may be a bit off topic, but I also thought about how this short scene would play out today if it was remade for modern audiences. It seems to be that modern audiences like to see the young triumph over the old, based on how the kids are smarter than their clueless parents trope that is part of many movies, sitcoms, and advertisements. I bet that the clip wouldn't end with the older guy getting revenge, but with the younger seeking and getting retribution.