Living here in NYC and being somewhat street smart it's rare that there is an area of crime I'm unaware of. After all we are on the cutting edge of crime, new trends often originate here and take years to get picked up on elsewhere.
I have not heard of anyone stealing ink out of printers to turn in for recycling for no money. Even the dullest people usually think crime through better than that.
The used and surplus ink I've come across is barely profitable if you get it for free, it's not a high crime/fraud item. Maybe some California Eco-terrorists would steal it to recycle. Or a gang of squid/octopi too lazy to produce their own in the ordinary glandular way. But those theories are unlikely.
I would guess that the competition is reporting you. If you are recycling ink that would otherwise go to the land fill you are doing a great service to the planet and to low income Americans who might not be able to afford new ink. But you are probably also undercutting people who buy new ink from a distributor to resell on ebay. They would like to see you go away and don't mind dirtying up their soul to do it.
That makes a lot more street sense than you running a stolen ink cartel. Unfortunately there is no viable way to combat it other then lay off selling ink for awhile. If the reports keep coming in on your listings you will get banned from selling. There is no mechanism for you to get justice, just an algorithm to identify you as a problem. Sometimes you need to shift focus a little here rather than get martyred on the cross of what is right and wrong.
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