Would mice/rats eat chinchilla food?

My sister recently adopted a chinchilla from her school's science lab to take care of over the summer and we keep it in our basement. Today, we noticed some kind of animal droppings near the chinchilla cage, but they appear far enough away that they could not be from the chinchilla. So we were wondering, if we do have rats/mice, would they be likely to eat the chinchilla food? Also, what else would they eat if they are living in an unfinished basement with absolutely no food in it except cans of soup (and now chinchilla food)?