No, I haven't been there but Sosua and SD are a bit different. They may have demand for 15 restaurants.
Of course not.
But it's not about turning a profit.
Those stores don't belong to persons running them, they belong to a higher authority who will use them to launder money.
Just like the pica pollos all over the island.
Almost all of them are required to buy their raw ingredients from one source. Haven't you even noticed the food is the same no matter which one you go to?
All of these stores have the same products too.
All of this is controlled by a Chinese network here in SD.
I was good friends with a chinese woman who ran a pica pollo next to my job. She was the one who clued me in on how it works.