I usually go to hobby lobby to buy my foam sheets, Walmart to buy skirts/jigs for crazy legs, and I have snagged the bead chain eyes off a broken pen at the hardware store. I have never seen that Idea with the bath mat though, I'm sure you could dye it with RIT dye. Do you know of any alternatives to foxy brush or tarantula brush? That is my biggest cost at the fly shop.And don't forget that you can tie your own flys with materials not sold as "fly tying material".
White shag bath mats make for a lifetime of craft fur if you are willing to dye your own colors.
Polyester yarn and two dog brushes will give you a lifetime of dubbing in every color under the sun
Bonnie macrame cord and two dog brushes will give you a lifetime supply of something very similar to EP type fibers.
Salvation Army & Goodwill usually have some beat-up fur coats, muffs, or hood collars from time to time (but PITA has kind of tapped out that source)
Squirrels and other furry critters are abundant, hunting buddies can usually come up with deer hair for you if you give them a heads up in fall and I will admit that when the neighbors moved out and left their fancy chickens behind, well you get the idea. You can also buy fancy chicks pretty cheap at TSC in the spring. It takes a while for that solution to materialize though.
I love my local shop but fly fishing/tying has been around longer than online shopping and most fly shops.
Learning to process your own materials can be another aspect of tying your unique fly.
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