if the person does not put in an address when they sign up, or pretty much anytime then it pretty much gives anyone the chance to say they didn't get the item sent, and you lose out on the points, and the item. Just do not want you to get burnt. Always make sure you send the items you list with delivery confirmation, that way again the person getting the item can't pretend they never got the item. The only person then who can get burnt is the person receiving the item if the seller send an empty package. Which in theory the buyer should record opening the package. Although that is a very extreme thing to have to do.