The cashier who refused you the sale was just doing their job. We HAVE to ID anyone we think looks under 25, easy to understand when you think how old teenage girls can look with make up, or teenage guys with facial hair. IME most people are fine about it.
Eg -
Me (scanning cider/wine/beer) I'm going to be a pain now
Can I see some ID please?
Either yes, sure or 'bugger I left it at home'
Me - smiling apologetically - sorry but I can't serve you
Them - no worries, my own silly fault
The ones who get defensive get themselves no where. I still won't serve them the alcohol and have no problem calling a supervisor over.
One memorable occasion, I refused a sale to two young people. The male had ID, the female not, he definitely wasn't old enough to be her dad (as obviously I'm not silly enough to refuse a sale cos their child is underage), I said sorry I wouldnt serve them . Man got arsey, I apologised and said I couldnt serve them, it's my job at risk etc/
Ten mins later an older gentleman came in, with the same brand whisky I'd refused sale of and asked our policy on alcohol. I happily told him, he asked why if he came in with his teen dd he'd get served yet his son had. Explained rules re proxy sales and not interfering with parental judgement and that 'the cashier probably thought there was a risk'/ He said that it was me, I agreed and said sorry but I stood by the decision. He shut up and left. The idiot. I was close to calling the manager over.
It's no fun for us Iding you. We never know if it's a genuine customer or a test purchaser and I have to act as though every time is a real purchase. Even when I'm asked to authorise sale for someone under 18, I make sure to take a good look at the ID and if they have none, I won't authorise the sale. I also ID groups of young people even if one is buying alcohol and keep an eye out - if I see for eg a group in an aisle and money changing hands, then only one of the group comes to my till I will ask to see everyoes ID and will again refuse the sale.
Maybe I wouldn't be fined for selling alcohol to a 23 year old test purchaser without ID. But I would get a reprimand, the whole checkout staff not just me would get refresher training, and I would be closely monitored for a while. I don't want that.
Though agree it is on stupid things. Including spoons (only possible reason I can think of is heroin use) and alcohol free beer!