I mean, I'm not imagining that they have groceries listings on the app, but that the app allows you to transfer money directly to someone from your crypto wallet. Like a venmo payment but with crypto.
The thing is that's not a novel concept, just about every crypto wallet app can already do this. And the achilles heel of all of these apps is the gas fees that are out of their control. The only way to conceptually get around gas fees is to keep everyones money centralized and sidestep the trading of crypto all together, but in the process you defeat the entire purpose of crypto.