Not defending Reddit, but it's the same with Facebook, and have you seen the Google Search results in a "developed country"? First full screen on mobile is ads that look like search results. Thankfully there's a small "ad" in the corner that no one can see.
I've come to the opinion that it's impossible for any free social media platform to avoid this unless the people running it are doing it as an act of charity. If you want to make money, you either make users pay or you sell access to / information from the userbase itself.