Seems like it would be the opposite. If you don't homebrew your own campaigns, then you'll need a steady stream of adventures or you run out of material. On the other hand, once you've got your PHB, you don't need to keep buying more.
Those of us who like playing with new mechanics do want an ongoing stream of splatbooks as well, but that doesn't require a lot of them. One book like Xanathar's supplies plenty of material to keep the game fresh for a couple of years. And even that is optional - we don't need the new mechanics in the way that a group relying on published adventures needs new adventures. We can keep playing with the stuff in the PHB indefinitely, we just start getting antsy after a while. A group that runs out of adventures, runs out of game.