Its not so much greed as in people are buying cheap tat just for the sake of buying stuff with no real thought about the recipient. For example I have I bag full of stuff that I got on previous cruises that I'm regifting on my next cruise, because its all kids stuff, when I am a solo adult.
Also people have set up small businesses and go around the cruise groups selling their home made stuff. People feel obligated to buy, as its a fellow cruiser, without any thought as to whether its suitable for the recipients.
Thats a perfect gift, thought about the recipient, easy to pack for both the giver and recipient and not an expensive outlay.
Basically think what the person you are giving to would to like to receive, be mindful about size and weight due to luggage restrictions.