I say if it speeds things up, either through mail or in lines, skip the names. Just bring a nametag or plan to put a label on your badge. Without names they don't have to sort or store the badges in any special way, they can just hand you any old badge and it will work.
I think it's a cost issue. Aside from the printing cost of "customized" badges, all the badge issues Eric mentioned are good cost reasons not to print names on the badges.