It's just passive (or mildly active) entertainment, nothing more.

Stuff is being "created", but it's not coming from me, and so I don't feel I'm making anything.

It is undeniably entertaining. Small children absolutely love it. "Make a happy face with a poo stuck to it" ... seconds later, bursts of laughter.

I think people get addicted to the stuff because of the inconsistent feedback. You never know how the next thing will turn out and it can take iterations to get to something "good".

If every time you threw a basketball at a hoop, it went through, few people would go on to play basketball; they would get bored in 15 minutes and forget about it.

People throw basketballs at hoops because they have just enough control to think they can do it, in spite of it mostly not going well.