Put yourself in the place of the grocer. If one person asked you to accept platinum as payment, would you? Probably no. If 10 people or a few loyal customers did, you might look into it.

Given grocery stores tend to use the currency corresponding to their government’s authorized legal tender for use in payment of debts: a lot of small things. A select number of stores in different regions accept bitcoin one way or another, word-of-mouth to support purchasing with Monero through similar systems can encourage practical consideration of it. It will take the slow expansion of Bitcoin-accepting businesses to also accept Monero as value that can benefit the business. In general, I don’t know of any specific grocery store in my region that accepts crypto, Monero has an uphill battle to see grocery deployment.

A better question is to ask how do we get a single farmer accepting and requesting monero usage.

The grocery store is a middle man that does little creation of value except occupying a location and marking up products to pay for electricity and labor, all of which must be paid in fiat by law.

Many farmers eek out a living off grid, and without any labor costs.

At this point the owner would have to be into Monero for it to happen.