I wasn't one of the people in this scenario but I was having this discussion with a friend who was.
There are five people out to dinner and they're splitting the billl. One person(my Friend) Karen has a gift card for the restaurant given to her by her employer. The gift card more than covers her share so she generously says that the rest of the gift card can be used to deduct from the bill for the other diners meaning that they'd pay around ten pounds less than they would have without Karen's gift card. One diner objects and says that the remaining bill should be split between all five(including Karen) and not the remaining four because she hasn't actually contributed any money to the bill, only a gift card that she didn't pay for.
It seems pretty clear cut to me who was in the wrong, but I'm curious to know what MN thinks?