You are misunderstanding things. It used to just be an actual t-shirt. But people who already had a t-shirt said they didn't need another one. So an equivalent amount of store credit was given to get something other than a t-shirt. I guess he could have just offered for them to pick from a few different schwag items. Any physical item as a thank you is going to have some sort of dollar value... but I still don't think that automatically puts it into the paid category.