A Ponzi scheme is where someone pays old investors using the new investors money and shows higher returns on investments than others. this is not what supercell is doing. instead of getting no returns you get satisfied with what you have done. Also imaging upgrading something like buying an iPad with increased storage for more money than a lower model, its the way economy works
Also many players, including myself spend time raiding resources not spending money on the game. spending money is only necessary to stay at the top leaderboard spot.





