"Everything from member discount cards at the grocery store..."

On that one small point alone, I recall an article in a magazine a few weeks ago, where it likened having a discount card for a supermarket to having a barcode stamped accross your forehead.
It gave an example of a man, having tripped and hurt himself in a supermarket tries to claim for damages. Apparently the shop involved checked his "history" from his discount card, and accused him, in private, that judging from the amount of alcohol he had bought recently (a period of several months) mean't he probably had an alcohol problem and that he was more than likely to have been drunk when he tripped.
The supermarket later backed down and denied that it had made that accusation.