Not a prank, just a funny story from high school.
About six months after the Yeshivas building was completed the massive hot water tank died. Still under warranty, the contractors sent a couple burly plumbers (who were apparently experts at plumbing, but not personal hygiene) to schlep out the old one and install the new one.
I commented to one of the plumbers that a brand new commercial hot water tank should last at least 12 months. Right?
In all seriousness he looks at me and says, “What do you guys do? Shower every DAY!”.
The rest of them burst out laughing at his sarcasm.