[mslot]

I doubt that's a significant factor in global green house gas production while plastic bags are a significant factor in plastic pollution. This seems like a basic optimization problem. Yes, this approach uses a tiny bit more memory, but a lot less CPU. Running out of memory is a problem, but there are likely other areas where we can save a whole lot more (e.g. eat less meat, don't generate demand for food that was shipped around the world).