Using found materials for your flies.
10 bucks for a feather?
In short the answer is no, in fact I use found materials probably as much as I do bought. There is something that just makes you grin when that goofy fly you named "Frankenstein" draws the eyes and opens the mouth of a quality fish. Not to mention how cheap the materials you find or come across in the day to day really are.
Meet squirrel dubbing
This stuff actually works great for flies tied on larger hooks. (14 or 15 and down) It is slightly thicker than bought dubbing but still maintains a solid amount of action in the water and the natural oils of the squirrel help the fly float. I tie nearly all my mayflies and stoneflies with squirrel dubbing. Just another way to make my small game hunts that much more valuable.