I was curious about it once when I was considering "hustles". One of the biggest issues may be finding a high-traffic location where you are allowed to operate a vending machine. But if a place could use one and will let you operate for cheap/free, you could give it a shot. One learns a lot from trying. Odds are the work & issues may make it tougher than it seems on the surface (may not be as passive as you think).
This is one way to find communities. Hopefully connecting the Fediverse becomes a little simpler soon...