I still think that the printer has bigger responsibility than the customer.
Remember, not every fan would have such knowledges on jerseys.
Some might be simply just a die hard soccer fan, not jersey fan, lack of jersey knowledge,
so they just go to the shop to buy/print their jersey to support their team, that's it.
End up the innocent soccer fan being laughed by others.....that's pity,
while the printer/shop still earning their money as usual, in fact very fine as usual.