It may seem at first that eating raw organic food is more expensive, but if you are serious about changing your lifestyle that would also imply that you will be buying less (or none) of the normal boxed foods, frozen dinners, cereals, canned foods, meats, milk, etc. that you normally might buy.
My late night snacks I used to consist of nachos or ice cream. Now I eat a banana w/some almond butter or an orange or a grapefruit. It costs basically the same (or less) now and is alot healthier. Good luck, Tom