I have been advocating, since 2015 to say the least, the introduction by governments, what I named "smart receipts".
Finally, the Greek government, starting in 2022, applied this idea in fighting tax evasion. The idea is to print a QR code on every paper receipt at the cash register.
This is achieved using the same real-time flow of information as when getting an approval for a credit card transaction. The customer can then scan the receipt using a smart phone and essentially allow the government to cross-reference all information in real-time, thus identifying merchants that cheat on their taxes and illegally hold for themselves VAT or sales tax that was collected by the merchant on behalf of the government. This not only helps identify cheaters but also makes the market more fair, namely, a baker who does not cheat, should not be at a disadvantage if the baker across the street does cheat. Please note that this is not an accounting system and does not need to be accurate to work efficiently and successfully.