That's why I buy from the stores that are "Everyday Store Prices". Stores like Costco have a markup but the app clearly says "Higher than in-store prices". It's kinda hidden https://www.instacart.com/help/section/200758534
I had to pester him a couple of times, file a BBB complaint and finally ask Google for the registered officer of the company since I was literally going to sue. That's when they filed a "remorse exception" that actually helped.
Also - ask for a "Specialist" - they're the only ones who can help. Every other guy is a "supervisor" at Google Fi support and they can't do anything. Had to call in more than 30 times and exchanged upwards of 60 emails. It's a shame.