Freemium games have evolved into one of the most lucrative models in the video-game industry, with mobile games and their in-app purchases generating about $7-$8 billion in iOS revenue last year. It isn’t limited to mobile, either.

League of Legends, the wildly popular multiplayer online battle arena PC game is “free-to-play” as well. But “free-to-play,” like “freemium,” doesn’t really mean free – last year, the game generated over $1 billion in microtransactions.

Like many “freemium” or "free-to-play" games, League of Legends offers players the core game for free and then optionally charges them for premium content such as in-game currency, extra content, or customizations.

Players in League of Legends can purchase new champions (characters), skins (customized looks for those characters), and influence-points boosts (which help you gain IP faster from playing the game, so you can buy champions without spending money).

Champions can also be obtained for free using influence points earned while playing the game.

Here are some of the champions you can buy in League of Legends:

And here are some of the skins you can buy:

Riot also often has sales and bundles like any retail store:

After the news was announced back in October, players on the League of Legends subreddit discussed just where all that money was coming from — namely, players spending thousands of dollars per year on added content.

One Redditor, DTSuteru, estimates that he spent about $2,000 since he began playing the game in March 2013.

Another user, cguo0516, estimates having spent more than $4,000 on the game over the past three years.

Other players' situations weren't as drastic. User Cloud_Rice estimates having spent $600 on the game over the last four years, while user Jagla estimates spending $200 over the course of two to three years.

One user had an idea how people spent so much money.

"Due to the way League of Legends works ... newcomers often benefit and feel good when spending real money. You can quickly lose track of how much has been spent and the true cost of what you are buying because of the genius 'RP' conversion [In order to purchase items, you must convert money to “Riot Points”]. The game has been designed to be a cash cow from the start,” explains user ElDanesh, who estimated spending around $200 on the game.

Here's what it looks like to buy "Riot Points" in the game.

One of the most interesting things about the thread is that, despite spending a large amount of money on a video game, the users were mostly satisfied with having done so.

"In all honesty, I really don't regret spending money on the game. You can legitimately play the game [without] spending a dime. The only thing that requires cash are skins. Anything else can be bought with enough play time,” wrote user Sw0rDz.

Here’s user Captain_Canadian’s justification for spending between $1500 and $2000 on League of Legends over the last five years:

It started as supporting a smaller developer, but it turned into me wanting to stay competitive but having less time due to school and work [note:While nearly all champions can be obtained for free with enough gameplay, it can take a long time to rack up enough “Influence points” from winning games to do so]. Thankfully I make enough money that it ended up being more worth my time to just pay for the champs/skins I wanted in [League of Legends] and just work a bit longer to make up the difference.

I would rather pay $1500 and keep playing a game I enjoy with friends than have to give up the time it would take to earn enough IP for the newer champs. In the end that's basically only about 30-40 hours of work for me so it's better than playing the additional hundreds/thousands of hours it would otherwise take.

Redditor Servalpur had a similar perspective:

I'm in a similar boat. I love League, but I also have a 9-5, a wife, and a 14 month old daughter. This all equates to me playing (at the most) 2-3 games a night, and more likely one game a day. I don't have time to [earn influence points], I am however an adult with a good job. A thousand bucks over two years is more than fair to me to enjoy a hobby I like so much. God knows I've spent more on sh*t I've enjoyed less.

Not all Redditors were happy however. Many complained that despite spending so much, the game still suffers routine game bugs and server outages.

"This just shows again how [expletive] people really are and how easy it is to sell them sh*t they don't need. Good job Riot, your pyramid is awesome and works,” wrote user ChaosCore.