Shoe stores, now they have a problem. They don't turn the inventory over but monthly or worse.
But McD's? They sell that hamburger a thousand times a day.
I don't think that is how margins work. Let's say you sell a unit of bread for $100, but you spent $99 the make the bread that's a 1% margin. If you sell a single bread per day for 365 days you earned $36500 and spent $36135 to make those bread. That is still a 1% margin.
That's what annualizing does. It's on the dollars invested, not the money thrashed.
If I look at that business in a year had $464 revenue and $99 cost. Investopedia defines gross margin as "(Revenue − Cost of goods sold) / Revenue" So that would be (464-99)/464=0.79. So that is a 79% margin. Below the 365%. Where I'm going wrong?
Look, I'm just making the point that comparing margins on a sale is a crappy way to compare business. It ignores the value you get for each investment dollar. Correct that by annualizing return per dollar. Then you see the relative value of business models e.g. McD's vs grocer store vs shoe store.
Restaurants too have slowly been gobbled up in my area of NY suburbs into larger groups. I think the Main St here with 20 or so restaurants is owned by just 3 groups.
Supermarkets are an incredibly low margin business and they would have to compete with existing players on those thin margins including titans like Walmart. There's not much more blood to extract there.
Independent mechanic shops have been dwindling naturally because it's too expensive for newbies to get into the field, especially between rent and needing all their own tools. End of day, formally "car shop" areas here are being bulldozed for luxury rental apartments.