It's possible to make all kinds of pies with very little fat. This greatly reduces the calories too. Most of the fat in your average pie is in the pie crust. Unfortunately, there's no way to make that flaky wheat crust without fat. When a recipe calls for a baked pie shell, however, here's a very simple and cheap substitute that works for most pies and is nutritious, as well.
Spray a pie plate or pie pan liberally with cooking spray; this helps the graham crackers stay in place and also helps to release the pie when serving it.Cover the bottom and sides with graham crackers, breaking them as needed. A few cracks and holes don't matter.
When pouring in the filling, spoon some in first so you don't push the graham crackers out of place.
Here's another variation if you really want a firmer actual crust. Place ten graham crackers, broken into small pieces, into a food processor or blender (or crush them with a rolling pin if you don't have either of those). Add 1 tbsp. lite margarine and 1 tbsp. maple syrup or honey. Process until well combined. The mixture should hold it's shape when you squeeze a ball of it.
I usually spray the pie plates with cooking spray first, but it's not required. Scrape mixture into pie plate(s) and press across bottom and up the sides until the plate is covered. Bake at 350░ F. just until edges start to brown, for an unbaked pie, or use "as is" if the pie will be baked.