I've had to cut a lot of things from my grocery bill lately. You can definitely eat potatoes and rice if it helps bulk up your meals for cheap. I've found ground beef for about $2.50/lb, and I'll eat 6-8 oz a day, and maybe 4 eggs in a day on top of that (2 dozen for about $5). I round it out with some vegetables that I saute in either butter or leftover fat (usually bacon fat!). Lately those veggies have been green beans, broccoli, spinach and collards. They are on the cheap right now at the grocery store. Try to go for bulk conventional veggies, as opposed to bags of pre-cut carrots, or salad mixes in bags. There is a lot less weight for more price for many of those.
The only real issue is getting bored with limited food for me. But it's no worse than getting bored with pasta and beans and rice etc. ever was... I'll try to spruce it up a bit on the weekends by having good bacon or sausage, but not always. If I could grow vegetables like someone else before me mentioned, I think I'd have pretty cheap grocery bills indeed.
Type 1 Diabetic. Controlling blood sugar through primal life.
Maintain A1c of 6.0 or lower
More dietary fat, less carbs, moderate protein
LHT and sprint as per PB fitness