Thank you for your very kind responses, @twinkledag @foamrolling and @poppadopolis .
Apologies for late reply, but l was at work til late last night, then been to work again today.
lt's all very organised now, l've had a lot of people use the word 'civilised' which is how it feels, in the main.
No more strops over "3 of each item only" except a minor spat last night when l had 3 adults doing one shop (why, l have no idea. They didn't have a huge amount of shopping, and one of them could have managed it). They had 4 of one item, and when l said they were only allowed 3, the woman said "We are shopping for 3 households here!"
Well in that case, love, use the dividers. l'm not a mind reader and l can't be expected to know that. lf it's true.
l have noticed a couple of families in today, though. One lady had her daughter with her, she looked about seven, and she stood with her hands on the checkout. We're having them cleaned regularly, but her mother didn't know that. She didn't tell the little girl not to touch anything. l felt obliged to say "Don't put your hands on the checkout, pet" to her.
Another woman had a smaller girl with her. While the mother stood and let her, the little one picked up toys off the shelf, ran her hands all over the display, and the mother didn't say a word.
Most people have been fine, with the exception of those who don't seem to grasp the concept of the 2 metre rule - we've got yellow tape at 2m intervals at the checkouts, and also a large blue dot (about a foot across) for customers to stand on while the previous customer is packing and paying for their shopping. l've lost count of the amount of people l've had to ask to move back, some have needed asking/telling several times.
Unfortunately it does seem to be the older customers (l'm 61 myself, l'm not being ageist) who don't understand it.
l had one very old couple at my checkout today, they must have been in their 80s, and both very frail. They really shouldn't have been out, but of course l don't know their circumstances. Our supervisor had to ask them several times to observe the social distancing. When they were ready to pay, the woman was standing right in front of me, leaning over the checkout. Both myself and the supervisor had asked her three times to stay behind the line at the back of the till to use the card payment machine. l asked her again, and she leaned right over, about 6" away from my face, and said "What?"
l've concerns for myself, but more for them. They were both so fragile and it really wasn't safe for them being out, especially bearing in mind their apparent obliviousness to the dangers.
Then, about half past three, not long before we were closing, a man came to my checkout. He was fine, observed the distancing, until he was paying for his shopping, when he said cheerily "l've just come back from Mexico this morning!"
My face must have been a picture, because he added "Well, we had to go! Or we'd have lost all our money!"
This is what we're up against. Most people are absolutely fine, very appreciative of us, and patient when having to queue and wait. But then you get people like that. l have to admit, it's spooked me a bit.