Reddit Blackout Planned In Protest Of API Fee Change, What You Need To Know
Yes, just like any major website, Reddit has an API, or "application programming interface." Applications can use the Reddit API to interact with the site in a more direct way than pretending to be a user. This is how all the third-party mobile apps for Reddit work, including Apollo, Reddit is Fun, narwhal, BaconReader, and RedReader—just to name a few.

Multiply that by a few thousand users and it's not hard to rack up a six-digit bill in a month. The developer of Apollo, the most popular Reddit app for iPhones, says that the new charges would cost him $20 million USD per year. Reddit says that the charges are "on par" with what they make off of the rest of the userbase, but the Apollo developer estimates that it's more than 20 times what Reddit makes off of a typical site or app user.
A huge portion of Reddit users, possibly even a majority, access the site through third-party apps. This is because old Reddit is a pain to use on mobile, new Reddit is an abomination before God, and the official app is laden with advertisements and a horrible user interface. Apps like the simple and convenient RedReader or the feature-filled Apollo give people a way to use the site without these frustrations.

As one of the commenters on the announcement says, "it's not hard to not break a website." Indeed, Reddit could leave well enough alone and continue making money hand over fist. The site had over $450 million in revenue last year, and admittedly, that seems low in the face of its 1.1 billion users, but discussion forums have never exactly been a huge source of profit for anyone.

Hopefully, Reddit gets the message. It would be a shame if the most popular English-language discussion forum in the world fell apart because its ownership simply got too greedy. There certainly are Reddit alternatives out there, but it sure is nice to have one central site consolidating everything.