I like how you think on that zero cost thing. And, it uses "scrap" that was probably just hanging around the shop anyway.
I keep two chocks for each side roped together. Obviously, the rope makes it easy to remove the chock from the wheel, but, having the two roped together means that you can simply get both done at the same time. And, if it has been raining, the rope is probably drier and/or cleaner than the individual chocks would be.
Bill