We were in our local branch of Winn-Dixie yesterday. As we paid the middle-aged female checkout assistant, the man behind us started loading a mountain of shopping onto the belt. He was red-faced, sweaty, clearly shopping for a large family, and looked harrassed and grumpy.

Even the most basic interaction in the South is slow and courteous. I'm still amused when Pam calls the electricity or phone company with some trifling query about our bill, and ends up gossiping for twenty minutes with a total stranger in a call centre in Atlanta about their husbands, children and grandchildren.

Me, I try, but I have decades of bad habits to overcome. In London, until a few years ago, paying for your goods in a supermarket was an entirely wordless transaction: you don't like being here, I don't like being here, so let's get this over as quickly as possible.

Then some senior executive from Sainsbury or Tesco went on holiday to France or Italy or somewhere, realised that customers there took it for granted that checkout staff would at least pass the time of day, and revolutionised the UK retail industry by introducing the practice there.

I also like the fact that some stores here have greeters. I used to be a bit cynical about this, but now I realise that if you're a big-box retailer it helps to give you a human face, reminding your customers and yourself that no matter how much of a money-guzzling monolith you are, you're still dependent on men and women with mouths to feed and bills to pay.

Anyway, back to Winn-Dixie. The normal greeting is "How ya doin?", to which the reply is "Good, how are you?" But as the man unloaded the first of a dozen boxes of breakfast cereal, he growled: "Tell me somethin' interestin'."

She looked as bored and fed up as he did, but her wit was still rapier sharp and she rose to the challenge. With scarcely a nanosecond's hesitation, she said: "You're our one billionth customer. Congratulations. Ha, ha, ha." Then she picked up her scanner and silently set to work on his Cheerios and Rice Krispies.