Comment by TeMPOraL

And you also need to refrain from breaking this scheme entirely, by introducing silly restrictions like only exchanging for in-store vouchers instead of cash, or demanding same-store receipt for original purchase (or equivalent) - like it happened in some places (e.g. my country, Poland) to glass and aluminum recycling.

Such restrictions seem to purposefully target poor people, and I have rather strong ethical objections to them (something about making a problem invisible and hoping it'll go away - or starve out), but the effect goes beyond that. Getting $20 back on a $200 product would be a different story, but here, it's more like $2 on $20, or $0.2 on $2; most people aren't going to bother with that (and understandably so: it's not worth the logistics overhead). So at best, all this does is redirect money stream from poor people to recycling companies. More typically, it just makes people recycle less.