Although these boxes seem like a good idea in theory, in practice they are'nt.
UNLESS, you keep it to specific states i.e. no overseas shipping (cutting out people on this site), you cut out new guys (hate the term newbie) as admin stated, etc. etc.
These boxes have been thought about on other sites I'm a member of and in most cases the idea was thrown out as it would end up being more problems than its worth, you'd end up paying shipping for a box o crap no-one wants and alienating members.
Just my tuppence worth