These days, Steam no longer offers an inventory option. This meant it was possible to sell the game by fetching it from your inventory, “gifting” it to another Steam user, and receiving payment from them for it via a third-party service such as Venmo or PayPal. Once you bought a game on the platform, you had the option to add it to your inventory before adding it to your library.

Has it always been this way? In the past, the rules on Steam were a bit different.