Food Budget

How much do you spend a week on food? The Pennywise Eat Local Challenge (SF Gate article) claims that the average is $10 per person per day. For a couple that means it is $140 for the week allocated to food. That amount seems a bit excessive to me. If I assume that you cook every day of the week (which in itself is unrealistic due to special ocassions, etc) then $140 seems like a lot of money. Our current food bill for the two of us hovers around $70-$100/week, depending on how much meat or seafood we buy. I wonder how the the budget of $10 is determined ... If we ate $140 a week (all purely cooking) then we'd never save money to go out to eat, go on vacations, etc.