The cost cutting is obvious, but helping the environment is where it really pays off. Recycling sand reduces the need for new sand mining, which protects rivers and beaches. Reused sand works fine for many jobs, like in concrete or as a base layer. This means businesses save on buying new sand and on dump fees for old stuff.
It's cool to see this happening with sand, because you spot the same idea all over now. My local cafe switched to reusable cups and their trash costs dropped by a third. These small material loops, from glass jars to old t-shirts becoming rags, add up fast when everyone does them.