What about a cash and carry where you can buy whole boxes of sweets they might do you a deal.

The supermarket where I work had a collection last week for our local foodbank and they donated 1/3 again.  There was also an appeal in the local paper for sweet treats for the foodbanks, in our store we sell the little bags of Haribo at 10 for £1 I think it was so my friends and I bought a couple of boxes and donated them ideal for Christmas stockings.