system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: April Fool's Day.

Why is this day dedicated to pranks and tomfoolery?
gpt
When you retire you can claim any April Fool's days you participated in for a modest tax break in most European and North American countries.

It's supposed to encourage more fun and happiness, as happier people live longer. Of course the actual tax break is hard to police, and a lot of people probably claim more pranks than they've done, but the system was probably built to deal with that. Also, interestingly, there's the guilt factor so people end up actually performing tomfoolery more than they normally would anyways. jk.