Reddit has gross adverts already: Huel, some self-help thing, naff Adobe ads endorsed by some Reddit superuser from a corner of the site I never read. I’d far rather they were relevant to the subs I do read.

If you could pay to remove them, would you?

I’d probably pay for a “premium” service that let me generically block stuff on Reddit - /r/popular is infested with a lot of stuff I’ll never be interested in.

I wouldn’t call it a racket though since it’s entirely voluntarily to use Reddit, or not use it. And there’s also the possibility to set up other competing forums, with or without ads.