It seems like people don't believe you and keep harassing you asking for what you really want, and then get really frustrated when you keep saying "No, really I don't want anything". Then they either respect your wishes and don't get anything, but seem to harbor some kind of resentment against you in their heart, or they get some random garbage you don't want and call you ungrateful when you don't like it.
Really the greatest gift of all would be some kind of exemption from this custom so I don't have to go through this twice a year.