That particular abuse should end after the Consumer Financial Protection Bureau (CFPB) warned on Thursday that it's illegal to force employees to use them. Still, the payment method isn't going anywhere, and may be part of a growing trend. 

Businesses, particularly ones with hourly workers, absolutely love these cards. They're a big money-saver for companies, helping them pay workers who don't have bank accounts or access to direct deposit, because they're cheaper than sending checks. Visa says that a business with 500 employees would save $21,000 a year by switching from checks to cards.