That one has irritated me since I was a kid. As a teen I saw a guy go nuts on a convenience store clerk about a purchase where he bought two items and the total sales tax was 3 cents. If the clerk had rung up the two items as two separate transactions, the tax on each transaction would have been a penny each. The customer would have saved ONE cent.I do get weary explaining why I can't just sell out the door without sales tax like they do at the gun show........
Over that ONE cent, I saw this old guy throw a screaming, spitting, cursing fit at the poor girl behind the counter. He actually expected her to run the transactions in her head first and them ring them up in whatever way would save the customer on taxes. As stupid as that sounds, he spent a couple of minutes yelling at her to teach her exactly that.
As a kid, that made a big impression on me. People for whom taxes are such a touchy subject that literally a penny will send them into a fit of apoplexy (not to mention people who try to steal big bucks via big fraud) have a screw loose that I'll never understand.