I once worked in a machine shop. There, a CNC milling machine is used to shape steel blocks into molds to make plastic utensils. The byproduct of this process is a lot of metal chips that have to be cleaned out at the end of the week. There would be bags and bags of those metal chips.
Guess where those bags go to? Right into the garbage bin outside. There's not enough metal for recycling company to want to pick up, and the owner of the machine shop see no point in driving to the recycling center. So, all the metal goes to the landfill.
This will never happen in China or Hong Kong where poor people would happily take away those bags of metal for free. The weekly amount of metal coming out of that machine would probably be enough to keep food on the table for those people for at least a month.