The entire story fits in the subhead: Cheaper for businesses to just toss returns than check if they can be resold.
The easiest way to change that would be to make disposal more expensive. Start a land filling tax (and/or a carbon tax, which would hit incinerators), and suddenly a lot of these businesses would run the numbers and say “never mind, let’s actually process the returns.” Or alternatively they’d say, “hmm we can’t make free shipping free returns work anymore,” which I think is also fine.
The easiest way to change that would be to make disposal more expensive. Start a land filling tax (and/or a carbon tax, which would hit incinerators), and suddenly a lot of these businesses would run the numbers and say “never mind, let’s actually process the returns.” Or alternatively they’d say, “hmm we can’t make free shipping free returns work anymore,” which I think is also fine.