We had our wedding Dec. 6th 2008 and we had a candy bar -- see image below..
I will say it is a lot of work and we were left with a LOT of candy, since we had so much food and then cake people didn't take that much.. My husband and I are big candyholics and thought it would be fun..
I will say if you are planning on doing it yourself, like I did, Disney does not allow any candy that is not wrapped (as part of their health code) and unless you get a REALLY amazing planner like we had, most won't set it up without charging you-- from what our planner told me..
Disney does offer to do the candy bar for you through the floral department -- but it is a tad on the expensive side..
All in all it was nice and I would say if you want to foot the bill and work -- I say go for it.. especially if that is what you are using as your favor..
I hope my 2 cents helps...