I took surgical tubing from the chem lab in high school (60s) back in the day to tie to forked branches . Unless you left them n the sun you could count on that thing shooting rocks clear through college. The first thing I saw when I was turned on to this new stuff is how far the act of slinging has come. It has become way beyond the scope of box stores and I doubt will we see it happen. I would compare it to firearm ammunition , if you can find it , all the big box stores carry it in some form but only specialty "sporting good " stores sell reloading equipment and components.