Sure. And if the experience of playing D&D and the experience of playing monopoly where one and the same, then you'd be absolutely right.
Analogies are always suspect, but you do realize that D&D is played on a different hand crafted board each and every single time it is played for each and every group that ever played it? And you do realize that the game can require hundreds or thousands of hours to play, such that it is an achievement to get the same people together week after week, year after week, to keep the game going on?
And so successful RPGs monetize tools to help people make those boards, not because they are greedy SOBs tricking people into buying supplements and modules and setting guides, but because people want those things. Because there is demand for those things. And the people that make those things are laboring to make themselves useful to their community. And we reimburse them for those things not because they cruelly demand payment from them, but because we are grateful and we want them to be able to keep doing it.