Well I had a princess moment in Borders this morning. I'd ordered a grande Earl Grey tea (with just one tea bag please: have you ever had two bags in a single cup bleurgh), and after paying, I asked for some soya milk to go in the tea. The girl behind the counter got it but proceeded to tell me that she would let me off from paying for it this time because she had already rung up the transaction.
Now I know that you don't have to pay for soya milk in tea; it only costs extra when it's the basis of the whole drink (as in a cappuccino or a latte). So I told her so. And she told me I was wrong. Which I wasn't. So I told her I wasn't. And it nearly turned into a contretemps.
It left me feeling a bit battered and bruised. I should know better than to enter into debate with shop assistants at this time of year: I've had Christmas jobs in shops and the last thing you want is for people to tell you that, actually, they know the rules of your organisation better than you do.
But I did know better and I can't bear being told that I'm wrong!