While this seems utterly petty, don't you hate it when customers come up to the till with their purchases and wave a gift card in your face, and say "I think there's £20 on here, but I'm just not sure" WHAT DO YOU MEAN YOU'RE NOT SURE? When you receive a gift card, it will have a receipt in it telling you how much is on there. Also, most kind gift givers will usually write inside the card how much they've given a person. Sometimes you just want to climb up onto the tills and scream "Get a sense of self confidence and certainty! THERE IS OBVIOUSLY £20 ON YOUR GIFT CARD!" (You're probably just PMS or something though, because this amount of inner rage over one small thing is totally unjustified...)