It's a fundamental way to learn.
E.g., suppose people tell me I'm a real funny person. Let me test that.
1. I remember a joke from a professional funny person widely considered to be one of the best.
2. I tell that joke to the people who told me I'm a real funny person.
3. I measure the laughter I get.
If the laughter is different-- e.g., if the people tell me this is by far the funniest thing I've ever said, then I know I've got a lot more to learn about jokes. On the other hand, if it's the same amount of laughter I usually get, perhaps I've got a real talent here.
Of course, it could be these are just close friends and they are primed to think anything I say is funny. Nevertheless, just the act of telling that joke as if it were my own gives me the experience of the timing and emphasis of that comic. It's a gain of knowledge.
That process is an order of magnitude faster on Reddit with control-v. Who know, maybe it even makes that person a bit more cynical about "karma" points. If so, they've at least become a less naive person.