One person's trash is another person's treasure. Cooking sprays are not cheap and you can never get that last drop out of the can. Save yourself some money and time and just re-use your butter wrappers. Once you've finished those sticks of butter, stash those wrappers in your fridge for later use. The butter 'grease' left on the wrapper is great for greasing your pans and trays for baking and cooking.