I track expenses on an excel spreadsheet. Here is what I got through 6 months YTD.... Actually less than I would have guessed.
Grocery: 3151 (121/wk)
Costco: 1830 (70/wk)
Restaurants: 1343 (52/wk)
Total: 6325 (243/wk)
If we take a costco trip and only buy grocery items I may plug it in the grocery line instead of costco line, but at least half of that costco number is non-food still. My wife also buys some cleaning supplies, toiletries, medicine, etc.. at HEB when needed. We are a family of 5 (2 adults, 5 yr old, 3 yr old, newborn (note - no food expenses yet)). Our eating out expense is probably mainly chic-fil-a with the young kids. With a newborn we haven't really had any decently expensive meals out or date nights.
We eat a lot of chicken/pork/ground beef so not much for expensive meats. Only seafood is probably salmon burgers from HEB that my wife likes. Costco protein bars are probably the biggest food expense... We both eat 2 a day so we go through the $18 boxes every 5 days.