According to this USDA data, richer countries tend to spend less on food overall. Of course there are factors affecting these conclusions, like the price of food and varying taxing systems, but the US still spends less than any other country in the world.
Although the average US citizen shells out about $2,273 per year for food, Pakistan still spends the most based on income percentages -- about half their annual income, or around $415.
Another interesting discovery is higher food spend is often linked to malnutrition. This could mostly be due to crop failures and droughts in poorer countries, leading to a raise in food prices.