What is DnD about if not friendship? Sure, there's also a fair amount of dragon-slaying, wizardry, and hand-to-hand combat, but who better with to do those things than friends? Imagine playing DnD all by yourself. You couldn't. The very essence of the game is collaboration. I recently saw a tweet that said something along the lines of: "The best feeling you can have with someone else is being in cahoots with them." That makes a lot of sense to me. To conspire with someone is to generate intimacy.
This is exactly what you do when you start a campaign with a group of friends. You become in cahoots with them and get to act out all your hair-brained schemes. It's like a (quasi) real-life buddy comedy. Whether you start as enemies or as friends, you're leaving with more in common than you have differences. That's exactly what these memes celebrate.