My uncle runs a Horse ranch were lots of guys come to learn how to ride Horses, race them, put shoes on them, etc.

My uncle is highly respected and loved by all the guys there. He has helped many of them who were confused about life or had hard times with their families growing up. He also feeds the ones who do not have as much money.

The only thing I can not understand, is this practical joke he likes to play. Sometimes he sneaks into their clothes and secretly rubs some hot muscle balm used for Horses inside their underpants.
So after a long day on the ranch, one of the guys will change his clothes only to discover that a huge slab of Horse balm has been slathered inside the crotch of his underpants.

The deep heating balm starts warming his sensitive areas more and more, until finally it feels like his privates have been set on fire. He frantically tries to cool himself down with water, but since the balm is oil-based, that only makes it burn even more.
Often the rest of the boys will ditch him and go to bed, and he is left alone out in the shower house with his privates burning, while everyone else is sleeping and resting up for the next day.

All the other guys howl in laughter whenever someone gets this prank done to them, and even the one who got the gag pulled on him never really gets mad!
I am also told the joke is usually played on the ones who are the most liked. However, sometimes the joke is also played on guys who are home-sick or guys who have a lot on their minds.

I can't figure this out. Why such a prank?

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