Ah, if only it was that simple. Companies just don't let you sue any more. (Including, I hasten to add, almost every single one of those darling HN graduates.)
https://www.instacart.com/terms
CTRL-F, "Arbitration"
> Mandatory Arbitration: If we’re unable to work out a solution amicably, both you and Instacart agree to resolve any disputes arising out of your use of the Services or these Terms through binding arbitration or small claims court.
> CLASS ACTION WAIVER: TO THE EXTENT PERMISSIBLE BY LAW, ALL CLAIMS MUST BE BROUGHT IN THE PARTIES' INDIVIDUAL CAPACITY, AND NOT AS A PLAINTIFF OR CLASS MEMBER IN ANY PURPORTED CLASS, COLLECTIVE ACTION, OR NON-PAGA REPRESENTATIVE PROCEEDING (COLLECTIVELY “CLASS ACTION WAIVER”). THE ARBITRATOR MAY NOT CONSOLIDATE MORE THAN ONE PERSON'S CLAIMS OR ENGAGE IN ANY CLASS ARBITRATION. YOU AGREE THAT, BY ENTERING INTO THESE TERMS, YOU AND INSTACART ARE EACH WAIVING THE RIGHT TO A TRIAL BY JURY OR TO PARTICIPATE IN A CLASS ACTION.
Sure, people will eventually stop using the service if the problem gets bad enough but as long as they keep the salami sliced[1] fairly thin, they'll get away with it for a long time with no outside check.