Food cost vary hugely in different areas, so what one person spends may have no relevance to you at all.
We spend about $140/week at the grocery store for two older kids and two adults. That includes paper products, toiltries, cleaning products and the occasional box of kitty litter. We eat out maybe twice a month.
I have no brand loyalty at all and house brands are fine, which is key to keeping cost down. I always read the flier and plan what I'll buy around that. I buy whatever is on sale and./or is cheapest. I stock up on loss leaders. I'll use a coupon if it makes the items cheaper than the house brand, which typically is only when the item is on sale, as the house brands are almost always cheaper than even a sale brand item.
I occasionally shop at Aldi, which I like very much for lots of things, but is a bit of a trip for me.