Ah ha interesting, but that is kind of ridiculous.
You would upload them to YouTube because if you're a nice enough person, you'd like others to share in on your fun. If you have a method of sharing entertainment, in this case YouTube, you will share your experience. It's part of the fun of it.
I do not have this perspective. But uploaders that make videos purely for fun have this reasoning.
Similar to how if children like their favorite toy, but share it with a friend because they want their friend to also experience the joy of the toy. Make sense?