A group of Democrats in the Senate have called on the Federal Trade Commission to investigate the tipping policy used by Instacart and similar services, which they claim are “allowing customers to deceive and shortchange shoppers.”

Instacart is a grocery delivery service that has come under fire for “tip baiting,” a practice where customers initially offer a large tip to shoppers but change it once the delivery is complete.

"People are facing unprecedented economic hardship because of the COVID-19 pandemic and so it is more important than ever that we protect people from unfair and deceptive practices," Sens. Brian Schatz of Hawaii, Elizabeth Warren of Massachusetts, Sherrod Brown of Ohio, and Chris Van Hollen of Maryland wrote in the letter, which was shared with CNN Business. "At a time when Instacart shoppers are most vulnerable, Instacart's service is allowing customers to deceive and shortchange shoppers."

The senators added in a letter to Instacart that they "welcome hearing from you about how Instacart is responding to these reports of 'tip baiting,' and what steps the company is taking to protect shoppers during this challenging time."

Instacart told CNN in a statement: "Our goal is to deliver a high-quality experience for both customers and shoppers. By allowing customers to tip after delivery based on their overall service, we see shopper tips increase or stay the same on 99.5% of orders. Additionally, since the beginning of the COVID-19 outbreak in North America, shoppers' earnings from tips have nearly doubled."

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