It depends on whether they really want to go through the trouble of authentication... Too much stress and holding the line etc etc...

Besides, they want to make the sales easier... So bring your credit cards ! - You can even steal your mum's !!!


PINs are not a good idea to float around at every transaction you do all over the world - credit card duplicators (people) easily trap these four digits and make a copy of your magnetic strips  - and you are screwed...


What these supermarkets do - is two things:

1) they dont care

2) if they do - it will be based on your behavior, ur dress code, or the amount you transact ---

A good conman will wear a suit - and shop for 50k.....
 
But if you left your house in a hurry, got into your car and drove down to the supermarket-  wearing slippers and a faded Celtel T-shirt,,,  and you did shopping worth 20k

- of cos they will be suspicious !