The keychains that Americans carry these days hold not just keys but also pocket knives, mini-flashlights, dog whistles, electronic buttons that open car doors, tiny stuffed animals -- even cans of mace to ward off muggers.
Oh, and little plastic cards called "club cards," "bonus cards" and the like.
In order to qualify to get the low, sale price on, say, a jar of mustard at the store, you must present your club membership card. The clerk swipes it over a scanner, which rings up the discounted price.
But the store gets something quite valuable in return: information about YOU.
When you obtain your shopper card, you provide your address, phone number, and, most likely, your social security identity number. Every time you shop, a computer matches that information with a list of the things you buy.
Companies say this helps them keep the products that customers prefer in stock.
But privacy advocates hate these discount cards, because they track sensitive purchases like pregnancy kits and because companies sometimes sell their computerized records. Yes we do, say the stores, but these are anonymous, mass data files that disclose nothing about individual customers.
Problem is, corrupt employees have occasionally been caught selling personal records, and hackers have spectacularly intruded into databases. And lost or stolen club cards put consumers at risk. To prove that point, a radio talk show host recently called a store and said she'd found a shopper card and would like to return it to its owner. She read the card number, and the company clerk blithely gave her the owner's name and address.
So while the little cards hanging from keychains open the world of discounts to consumers, they can also reveal customers' secrets to the world.
This is one of VOA's Only in America radio essays on events and trends that are peculiarly American. To visit our Only in America home page click here.