Imagine, you get together with your friends, have some snacks, and then you all transform into powerful wizards, rogues, paladins, and barbarians. And you get to be those people for a couple of hours. That's exactly what happens when you get together to play Dungeons and Dragons. You get to transcend your regular physical being for a while. You get to shake off the burdens of being Jake the insurance adjuster, or Beth the med student, or Tom the preschool teacher. Normal life can be so utterly boring. You need little chances here and there to try on a new persona.
Most people just do that on Halloween, but DnD players get to do that every week. And on Halloween. It's an important psychological tool, not to mention a way to bond with your buddies. And while you're waiting for your next session, you can send these memes to each other to remind you of all the fun you have.