Do we really want everything that we buy to be a matter of record to be recorded and saved for indefinite period of time by banks and credit card companies? Amsterdam especially has services and goods on sale which might not look too good on a credit card bill. Even if all you bought was perfectly legal, who knows what conclusions current and future databases or officials will make? Will I receive an "enhanced" security check if I buy box cutters on the way to the airport?
While such shops are rare now, they might become more popular unless people are aware of the loss of privacy, and potential for abuse by unscrupulous people with access to the data. At least currently I have the choice of paying cash. I don't want that choice to be taken away, replaced by an ever-wider reach of the surveillance state.