I've heard the opposite from a wolf biologist that they actually don't eat stomach contents of larger prey but I do not know it to be fact.
I do think a lot of kibble and other dog foods(and cat foods! Cats definitely do not need veggies!) have way too much veg and fruit matter. Seems to be more for us then them.
~Ollie vom Grunenfeld HIC(8/29/2012)WGSL/WGWL/DDR cross - herding dog in training!