alt Hacker NewsAgreed, this is totally solvable. You could even set up an email address for people to send pictures of their receipts to so they know who to investigate. Imagine if you could just screenshot a bill and send it to "[email protected]" and then they'd assign someone to look into it!
Also pre-emptively accepting defeat is by definition self-defeating.
You don't know it won't work if it's not actually tried and as noted there's no particular reason to think it can't work.