They sell at sales etc. but...I'm thinking that you are thinking of more bulk sales. Like Restaurants and such ?
Shipping by air has gotten to be such a hastle now in canada :
http://www.thatquailplace.com/smf/index.php?board=31.0I had some more info to post on the types of containers needed, but have yet to remember to get copies that a person can read properly. (I will no longer ship by air)