Living space is small, so many gifts will take up valuable space.
All ships have crew shops that carry chocolates, muchies, also vending machines that sell phone cards that crew can use from their cabins on the ship (that take $10 and $20 bills). Guests bring and leave a lot of personal products (i.e. bath & body products, etc) so those who work cabins tend to pick over that stuff before it goes to the incinerator room. And the shops onboard have perfume/booze/trinket sales below after every payday . . .