> They care if a receipt was generated by the machine, and are a check on the employee.

Aren't receipts used to track the store's revenue, as in the numbers reported to your local tax agency?

As far as I know, it's common for cashiers to have a daily/weekly/monthly slack value that they are allowed to report as a difference between the number reported by cash registers and the amount of cash delivered, because SNAFUs do happen during a day's work.

This could be stored on a computer now, though. But numbers can be fudged.

Taiwan had an interesting way around this with a receipt lottery. Ask for a receipt, it has a number on it that enters you in a lottery. Presumably the generation of this number means the sale was reported.

https://guidetotaipei.com/article/taiwan-receipt-lottery-%E7...

Portugal and a few other countries have that, too, it's very effective.

https://www.economist.com/finance-and-economics/2019/02/28/g...

It is pretty important to do mid-shift counts randomly as well. A common scam is for the cashier to ring no sale if the total is an easy price, say $2 for a coffee. Then mid shift the register will have extra money which would have been pocketed at the end of the shift. If there is too much money in the register, the employee is skimming.

Just as business owners don't trust their human cashiers, governments don't trust business owners.

In my country, the cash register of every company that makes over x amount of annual revenue is connected via the internet to the taxman.

In the US, the govt outlawed the software contracting industry in the 80s because they suspected people weren't reporting their earnings when they filed their taxes. forcing everyone to become employees of companies that were better monitored. I suspect the same motivation is partly behind the attempts to eliminate other kinds of gig work now.