Gig workers are fed up with being treated as second-class citizens by store workers

Evelyn Hockstein/The Washington Post via Getty Images

• Gig delivery workers say store staff can make shopping for apps like Instacart much tougher.
• Employees at supermarkets and Walmart stores often ignore gig workers — or berate them.
• It's part of the job customers usually don't see, but one that can affect orders, shoppers say.

Most days, a driver for Walmart's Spark...