Which brings me to my second question - do providers make any real money from building these bonuses if only the fake money streamers play them? Maybe they are purely there for marketing purposes to get us real players to try the game (non super bonuses and all-or-nothing spins etc)?
So splitting this into two parts...
Regarding the monopoly money streamers themselves - it'll depend on the deal between operator and provider, by default you would expect the provider cut to still be due (e.g. 0.5% of wagers).
The most curious part of the early Drake x Fake x Stake streams wasn't his complete disinterest in "$500k+" roulette spins, or even the comical overreaction when he "won $10m"... but when Pragmatic Live went down. He started scrambling, and even when he played Evolution for a couple of minutes he was stalling and constantly checking if Pragmatic had come back up.
To me, that suggests there's some kind of deal in place - and prefer to spend a few hundred a spin with Pragmatic, then a few thousand a spin with Evolution... because that cost
is real (and likely the only part).
Regarding the wider ecosystem - you can see how much certain providers (Pragmatic, Relax, Push, NLC etc) are pumping effort into the monopoly money streamers, to build "mindshare" with audiences that tend to skew younger.
So not only are they pushing their brand ahead of others, but then they offer you a solution to the problem they caused where the base game is dull as dishwater, so much so that you
want to skip that grind and buy the bonus instead - a trait introduced by predatory microtransactions in video games, and borrowed back by the gambling industry.
I enjoyed some of the early offerings from NLC, Relax and Push, but the later streamer slot offerings are dire. There will be a strong correlation between those that can bonus buy, and those that play those games... and that'll tell you what they are chasing! The outcome of which is entirely predictable...