We nearly exclusively buy at the Wedge and very occasionally slack off and run to Whole Foods, so we definitely pay a lot on the individual items. I figure Matthew and I run on average right now around $56 per person per month and I actually thought that was a fair amount until I saw other people averaging potentially up to $90! Wow. Matthew thinks this difference is because we don't eat much meat but do spend on things like large quantities of milk (like a gallon and a half a week of Cedar Summit). Groceries are the third largest expense in my budget, which I think accurately reflects how important eating well and contributing to healthy food systems is to the both of us. We reduce our overall costs by buying in bulk and reducing as much pre-made stuff as we think is sensible: dry beans, canned tomatoes instead of spaghetti or pizza sauce, etc.
We average about $45 per person per week, eating mainly all organic food (including grass fed beef/dairy). Buying in bulk helps a lot, along with finding really great recipes online. I find that the cost of eating is influenced by the type of diet you have, so I figured I'd share - not everyone pays the organic prices.
Keith and I were averaging about $50-60 per week before. We recently got a membership at Costco that we are splitting with my mom. This has brought our average grocery bill down significantly. It hasn't been long enough to get a good trend but I would estimate that it will ultimately put us under $30/wk as we gradually accumulate pantry items. The nice thing is we eat really well, but buying in bulk really brings down the costs.