Originally Posted by sinizter

First, never buy more than 8-10 in a single transaction and ask them to press sub-total after each card is scanned. This reduces the chances of cancelled cards.

Secondly, some Tesco stores have made up rules of their own and some staff have even worse made up rules. You just have to put up with these people or not buy them. If you tend to visit the same stores around the same times, you will work out which SAs are better and just go to their tills instead of the one that may appear shorter …. Teenage looking ones are good bet as they tend to be completely unconcerned about policies, etc and just want to hear a good scan beep.

Sometimes, it just is not worth the hassle.