remember sweet fruits are not a good idea with campbells and hybrids, and if you have a pale coloured hamster and you wish to show it carrot, blackberrys etc are not good ideas any time near show time, they can stain for weeks
personally mine usually only get fruit and veg when they are traveling/at a show, when an additional water source is needed. A good diet will include all the nutrients etc they need without them needing any fresh added... that said if i have some veg left over they get some at times, or nursing mothers...but its not a regular planned in treat