In my experience they often seem averse to typing sales into a cash register, even when they have one right in from of them....or the ole "type the price in and hit "cash" " trick.
My grandfather ran a store that my uncle took over. No pennies, no tax. Everything was priced as marked. End of the day, count up the register and write it in the log. end of the month calculate how much came in, multiply by sales tax, and send a check off to the state.
Maybe they're cheating. IMHO, most of that cash register discipline is because the owner (or his immediate family) isn't running the register.
Im sure you can get away with not paying taxes for a while, but if you're going to have a generational store, you've got to be honest.
Technical controls are cool and all. When you can just look over and see you need more cans of soup, when you implicitly trust your employees, and you're not looking to make a quick buck and run away, they're just a lot of work for not much value. Scaling has a cost.
In South America, tax evasion has evolved so much that there are software packages with built-in "under the table" accounting, and dual accounting (one for the state and the real one).
Paying actual taxes is a fast way to bankruptcy here :( , the above-board companies look for tax loops, smaller ones make do with dual-accounting and understating income.
Government figured out that income tax is the most difficult to fake and heavily hammers employees :(
Most people in their communities are fine with it.