Instacart’s tipping system is getting some new scrutiny from Congress. In a pair of letters today, a group of senators led by Sen. Brian Schatz (D-HI) raised concerns that the service’s tipping system may be unfair or deceptive and called for a regulatory investigation of the practice. One letter sent to Instacart CEO Apoorva Mehta took the service to task for allowing buyers to promise large tips but reduce them to zero after an order is fulfilled. “People are facing unprecedented economic hardship because of the COVID-19 pandemic,” the senators wrote, “and so we hope online delivery companies like yours are taking the necessary steps to protect shoppers and prevent unfair and deceptive practices.” Reached for comment, Instacart defended the system, arguing that it typically increases the...