King Addas loves charades, and has a troupe of mimes in his harem. To ensure that they can never cheat he has had their tongues cut out, which is why they always look so miserable and never open their mouths (the stump of a tongue is not a pleasant sight).
The Nomin gypsies have a fiddling competition every year, known as the Danse de Velose. Beaters hit out the rhythm on taut drums and the competitors start to play, slowly at first. Youngsters can compete, but are soon pulled away by worried mothers, before the competition becomes too dangerous. After two hours the haunting tune has become dazzlingly fast. You can resign at any time, but the moment you make a mistake you receive an arrow through the neck. Strings may snap, but the players must play on. The whole affair never lasts much longer than three hours, and the last fiddler playing is crowned king of the gypsies.
An artist is commissioned to paint frescoes in a cathedral, and is imprisoned because of his unconventional style.
In ancient China, women bind their feet for cosmetic reasons, resulting in them not able to walk without help and walking in a shuffling gait.
Possibly this can be modified such that people do it for less stupid reasons.
Disclaimer: This is NOT a racist remark since I'm Chinese myself and hence entitled to freely judge Chinese customs. NOT sexist either since I'm female as well.