For the same reason that all of us post in these forums. Humans are social creatures who typically have an urge to share our experiences with other human beings. I imagine the drive served us well early in our evolution when it would have allowed us convey information about where food and shelter could be found and about what that food might look like. And we have used images to do that since pre-historic times. Think cave paintings, for example.  

These days we still have the urge to share. But we also have instant image generators in just about everyone’s hands because cell phones with cameras are ubiquitous. And there are now so many of us that when we tell others where to go, we can end up with so many of us that we end up damaging or destroying the place.