McDonald's is way more expensive than lean chicken and other meats, or fruits and vegetables, beans, etc.. Cola is also more expensive than water. I am not buying this notion that healthy food is too expensive or in short supply.
Anyway, two blocks away I can buy in McDonald's a complete meal for each member of my family, or I can go two blocks in the oposite direction and buy a roasted chicken with fried potatoes that is good enough for two or three meals of my whole family if we add rice or microwaved potatoes, that don't require too much baby siting.
Green salad is difficult, because it must be fresh.
My most recent addition are roasted red peppers, that can be prepared in advance and frozen.
When Dave's is the only place to go, there's no pressure to keep the prices down.