A decent size grocery store I assume might take $100,000 per day. Theft losses of 1% sounds very survivable - especially when all other stores in the region have the same theft losses, so prices can go up by the same percentage.
There's lots of Walgreens that accept SNAP though, ~8700.
The operating income for Walgreens in the US (retail AND pharmacy, including mail order, but I dunno if Gross profit would be a better metric) is $324,000,000 across around 10,000 stores. So around $100 per store per day.
Of course if you are walgreens, then you are not operating to break even, you have a given cost of capital that requires a return greater than 0%, as an investor could pull their money out of walgreens and buy federally insured mortgage bonds and make about 2.0% risk free.
But investing in walgreens bears substantial risk and volatility, so they expect returns of about 6-7% to compensate for the possibility of losing money. And most stores generally invest right up until they reach that threshold, so really any shoplifting that is out of what the store projected and budgeted for in their original investment calculation may be enough to close the store.
In other words, there is no "free" money to be had. Just because a company wont go into the red if only $100 a day of extra costs are imposed doesn't mean the company can afford to keep the store open, as it is answerable to opportunity cost, not just break-even requirements. Even if a store is making money, the scrap value of closing the store and selling off the land, moving the inventory to stores in other states where it wont get stolen, etc, is such that it is more profitable to close the store than to keep it open. And it may even make more sense to expand in new growing areas where police keep shoplifting in check and pull resources out of the legacy locations where shoplifting is high. This is also one reason why you get "food deserts" and other types of areas where retail doesn't seem to be able to survive or only survives by charging extra high prices.