In DH when Harry, Ron and Hermione are on the run, the lack of food is a major plot element. I was never terribly bothered by some of the other inconsistencies in the HP world but in DH, it always seemed glaring to me that while Harry and friends are going hungry or eating horrible mushroom soup, Ted Tonks is able to easily use a summoning charm to capture salmon.
"Reckon there's salmon, or is it too early in the season? Accio Salmon!" —Ted Tonks
I don't think the question of if it is "too early" for salmon mitigates the inconsistency. One assumes there are other types of fish in HP world, along with rabbits or any number of other animals which could be eaten and could have been summoned by Harry et al. Is this a case of Tonks being a more mature wizard and knowing how to live rough? That also doesn't really satisfy given how clever Hermione is.