Both my kids have Osper cards. One is 16 the other 14. Frustratingly Osper blocks any shops that sell alcohol so they frequetly cannot buy from cafes or the like. My son (16 yr old) went to boardmasters and couldn't buy anything from any of the food stalls.
Find it a bit overly big brother of them doing this. Am in the process of getting a Starling account for my son but this is truly aggravating for them as it stands.