I've got an AirBaltic "BalticMiles" membership card, as well as an ANA mileage club card, and an Hilton HHonors Silver card. I'm registered to many more clubs, but these are the only cards that I've been given. Anyway, are they really needed? I'm departing for a 1-2years of traveling (ultra-light), and trying to get rid of any items that I do not really need. Are these one of them?