Starbucks strikes
A union drive at Starbucks also resulted in stoppages that began Friday.
Labor group Starbucks Workers United announced "escalating strikes" through Christmas beginning Friday in three markets: Los Angeles, Chicago and Seattle.
The group, which has unionized more than 500 stores across the United States, argues that Starbucks has "backtracked" on commitments to bargain productively on a contract.
But Starbucks described as "not sustainable" union demands for an immediate 64 percent hike in the minimum wage, with a three-year increase of 77 percent.
"There has been no significant impact to our store operations," a Starbucks spokesman said Friday. "We are aware of disruption at a small handful of stores, but the overwhelming majority of our US stores remain open and serving customers as normal."
The union said the strikes would expand to locations in the cities of Columbus (Ohio), Denver (Colorado) and Pittsburgh (Pennsylvania) on Saturday.