Since all payments are going directly to the devs account, it might be hard / impossible to distinguish the difference between "cheap" and legit one
Since the payment have to do an in-game-purchase, IMO there is no way to buy cheaper gems without hacking through the system. I think
3. Purchasing of “cheap” gems is 100% SCAM.
This is just me sharing my bad experience on other games with those kind of sellers (not mobile game btw) :
Those selling "cheap" gems pay normal amount to the developer (
this is only happen if they are not scamming), however the money they used is not theirs (carding / stolen cc, etc) , so you still get what you bought on much cheaper rate.
hence my question on earlier post ,
is it possible to do dispute on payment made through appstore ? , because if the real owner of the cc dispute the payment
and win, the devs wont receive their money. And your account will be most likely ended up locked / banned ( this was my case on the other game ) ,If you cant dispute payment on appstore tho , then its all about morality..
All that said , buying from those "cheap gem" seller will only pose yourself to risk of being banned / scammed