Spreading the food dollar further by kelhan
I've just come back from Paris. We spent a large part of our travel budget on food. But we were working with almost double the dollar converting our Australian Dollars to Euros. As already mentioned, there are lots of street vendors where you can buy food to eat while walking around (something a lot of people in Paris do). There are supermarkets, but by far it is more fun, and the Parisian thing to do, to shop in the market streets, such as Montorguiel, and get some fresh bread from the Boulangerie, fresh cheese from the Fromagerie, and fresh dessert from the Pattisserie.
If you are finding it hard to stretch those dollars, there is a soup kitchen in the back of St Eustache Cathedral, near Les Halles. We didn't eat there, but we walked past it every night on our way "home" and it smelled delicious!