sure yeah, we need sand for erosion control, but getting it from glass that has already been manufactured (a carbon intensive process) and turning it back into a raw material, instead of remelting it into more useable glass, is a strange idea.

normally we take a raw material, and (with effort) turn it into a product people use, and if it can be reused after its first use, it makes a lot more sense to work on that, rather than turning it right back into raw material.