A-HA!!
Good grief! I didn't think a lot of 'sugar' was good for chickens...no wonder she's smelling that sicky sweet smell...aaaack!!
I think they use it as a binding agent. It is the last ingredient, so there can't be much of it. Molasses is a common feed ingredient, and in poultry it can be used in higher doses to help "purge" their systems ... in smaller doses it binds the feed and it has a lot of minerals and such. The birds do like it.
I agree, I don't think chickens "need" a lot of sugar.