On a budget, and for people trying to limit their saturated fat, cheese works best as a flavor-enhancer rather than a major source of nutrients. IE don't bother with pizza or macaroni & cheese dinners, but sprinkling some parmesan on your meal can make it taste a lot better without really adding a calories or costing that much. (If your goal is ridiculously low, like $1.70/day, it's probably still too expensive, but since the upper average is probably closer to $15-30/day there's plenty of wiggle room)