Every week we get supermarket flyers in our mailbox. One shop regularly offered a 4 euro reduction voucher if 40 euros was spent in their store. We made it into a regular weekly activity.

My husband is excellent at mental arithmetic so it was his job to total up the purchases until we got just slightly over the target amount. It would not have been profitable to spend 50 euros as the 10 % would only have been 8 1/2 % off. (I told you he was good at mental arithmetic!)

The problem was that our calculations and the shop’s calculations were rarely the same. We would arrive at the tills to find that we were either 20c short and had to quickly run, so as not to annoy those in the queue behind us, and find a packet of peanuts to bring us up to and over the thresh-hold or we were over and buying more than we needed;

We soon learnt to take a pencil and a paper on which to list the items and their prices so we could see where we had gone wrong. However, when we checked the till receipt against our list we could see that each week several items were marked at one price on the shelf and another price at the tills.

In France, as in the UK, the law is clear. A shop must sell any product at the price shown on the shelf label, if that is less than the price at the till. We would regularly point out these discrepancies to the staff especially if we were being overcharged.

Eventually, I had a collection of till receipts that I had annotated with the errors . I scanned several and wrote to the shop’s headquarters.

In the post I received a letter of apology and a voucher for 5 or 10 euros – I can’t remember which.

When I next did some shopping and presented the ‘bon d’achat’ the lady on the till looked at it with astonishment. She asked where I had got it from. I replied that it had come from her shop’s headquarters. ‘ I’ve worked here for 10 years, but I’ve never seen one of these before’.

It was then that I realised that French customers rarely bother to complain.

The manager got more and more irritated with us pointing out the errors. One day He angrily took my paper out of my hand, disappeared for several minutes and reappeared having changed all the wrong labels, saying ‘There, they are all correct now!’

That shop closed down soon after – the whole chain disappeared from France. I would think that competition with Aldi and Lidl had become impossible. The manager now works for one of our favourite stores which is also a German owned chain. I was a bit nervous of contact but always said ‘hello’. He greeted me with a friendly reply one day when I complimented him for watering the plants on sale – something that rarely happens in any shop. He now greets me with a nod of acknowledgement. I expect he has realised that the management of his former chain did not make life easy for their staff. Working for a German chain is probably a lot less stressful. We can say hand on heart that we have never found any discrepancies between the shelf prices and the till prices in any of the several chains that have taken over France, and the world, with their legendary teutonic efficiency.