How games are monetized has changed a lot throughout their history. In the 70s and 80s the average price of a game at release was $40 (although there was a lot less consistency compared to today.) The first major home console was the Atari 2600 in 1977, if we adjust for inflation a $40 game would be about $210 today (2024). From 1993-2005 the average price of video games at release was $49.99. In 2005 with the release of the Playstation 3 and Xbox 360 games would start to cost $59.99. In 2020 with the Playstation 5 and Xbox Series X, AAA games began to cost $69.99 at release. What will be the event that moves games to $79.99+?
In the early 2000s is when video game monetization began to take new forms. The early 2000s was the birth of the indie game development scene. Indie games existed prior to this time, but were usually created by hobbyists. This changed in the early 2000s as smaller companies began making games. These games range in price, usually much cheaper than AAA studio releases.
It was also common in the early 2000s for companies to release consistent game updates after the game released. These releases cost the company money and so they needed to continue making money after the game had already been purchased. In 2004 Blizzard Entertainment released World of Warcraft, which required players after they purchased the game to pay a monthly subscription ($15) to continue playing. Many other games would try this method unsuccessfully.
Before fast internet was widely available games would release expansion packs. These expansion packs were add-ons to existing games and wouldn't usually cost as much as a full game. (You would have to go to a store to purchase them.) These would become what modern downloadable content (DLC) is today. The name DLC would be popularized with the rise of map packs for Call of Duty and Halo as well as song packs for Guitar Hero. These DLC would allow game companies to continue making money on games without a full development cycle.
Eventually, DLC would lead to the idea of season passes where you would pay upfront for additional content that would eventually come out. (Sometimes.) This is very similar to games coming out in early access, where consumers purchase unfinished games in the hopes that their money will help the developers finish the development process.
Free-to-play (F2P) games became popular after many games failed to make a subscription model work. F2P games are free to begin playing, but have an in-game store where you can purchase items. These items are usually cosmetic or resources/currency for the game. These purchases would eventually become known as microtransactions. This format became very popular for mobile games.
Another form of monetization in modern games is different editions of games. These special editions often come with some in-game content along with physical/digital material related to the development of the game such as art books and soundtracks. It is also common for statues or toys to come with these editions.