Foxes eat berry's and fruit in the wild.
Lots of domestic dogs love fruit and veg but we often don't think to give it to them. We had to fence off the strawberry patch from our Alsation as she ate all the ripe ones, checking each day to see if more were ready for her. See was great with picking gooseberries and raspberries off the bush too - much quicker than us. I think she could smell the fruit that was ready for eating. She would just leave the 'core' of any ripe rasberries hanging on the bush and she never seemed to get scratched by thorns when picking fruit, even deep into a gooseberry bush.
My mother always had to buy extra carrots, as if she was preparing them, our dog would sit and cry until she was given one or more from the bunch - she would go through loads in a week. She would go to our apple tree as well (some distance away) select a fallen apple and carry it back to the house where she could eat a bit at a time while watching the view over the fields.
Never give them raw potato though as its somewhat poisonous uncooked, both for dogs and for us.