Distill it down even further: everything online that promises any kind of reward is a scam.
Why only online?
Offline it takes a lot more effort.
It’s much harder for a 49 year old man to pretend to be 23 year old woman to try to get you to buy feet pics in real life vs online.
Because offline it's possible to punch a scammer in the face. There are still many offline scams, but not as many.