I’m the kind of person who likes to experience everything a game has to offer, so I always sit through the credits the first time, reading the names and listening to the music. It’s like a reward for finishing the game. I will usually watch them in full on every subsequent playthrough too, unless they’re exceptionally long (I’m looking at you, Mass Effect 3).
Besides, nowadays many games include entertainment elements during the credits. My personal favorite is the Troy Baker/Courtnee Draper “Will the Circle be Unbroken” jam session during the Bioshock Infinite end credits. That was amazing, and a wonderful reward for completing the game.