It seems like many low cost meals are filled with pasta, rice, or bread.
It's that way for us as well. We don't follow a low carb diet for weight loss but for health reasons.We have to have a balancing act between cheap and healthy.
Most of my dinners consist of a meat, a veggie, one starch/carb (potatoes, rice, pasta or bread) and a salad. I try to keep brown rice, sweet potatoes, wheat flour and wheat pasta on hand for the starch portions instead of the white counterparts.
My husband who needs the low carb diet will have a larger portion of meat and salad than the rest of us. We use more of the starch serving and cooked vegetable as filler for us.
I also will use some higher carb foods and some processed foods as fillers for the kids and I. I am careful about doling these into the menus though so we aren't eating too much.