They don't buy shields. Shields have a cool down period. They leave their clan. Have a clan mate go offline with defense separated. Then they attack that clan mate for 1 star (free trophy) then they have their clan mate revenge them and only do 40-50% damage for another free trophy and a free 12hr shield. Most of the trophies that they have we're not earned but given to them by fellow clan buddies.
The only real work they put it was to get near the top. But since that point it's been nothing but cheating to move up.

