The agency said that drivers on Walmart's Spark platform couldn't immediately access their earnings without giving the app a cut.

The Consumer Financial Protection Bureau is suing Walmart and a finance company, arguing they forced delivery drivers to fork over junk fees for “costly” deposit accounts and used their personal information without their consent.

The U.S. consumer finance watchdog accused Walmart and the workforce payments company Branch Messenger on Monday of forcing more than a million delivery drivers into using accounts that cost them more than $10 million in junk fees.