Many people think they need multiple controllers to play their favorite games. Many people believe they need all the accessories to be able to play their favorite games.
You don't have to own each controller. Most games these days use one controller per person. Multiplayer games can be played with only one controller.
But if you really want to get into the action, you'll need more than one controller. You may need two controllers for certain games. So if you want to play those types of games, then you'll need to invest in additional controllers.