Well Chip, 'I doubt' as you state makes it evident that you are guessing, like many on here. And I am also not guessing that I am talking about your friends little independent store. We are talking about large chains, the DR imports the crap no one else will accept, and exports the fine quality stuff it produces. The DR takes anything at the reduced price, clothes, toys, FOOD.
So yes, there are places that do sell local produce. It would not be financial sensible to import huge quantities of second rate food. But it is cheap than buying local for the large chains, so no, I'm not guessing. {Dog passes the salt around}
The large supermarkets don't have the majority market here in this country, therefore by far the majority of the produce bought sold and consumed is criollo.
Your problem is you live and think like a foreigner, as evidenced in your posts, and thus have little clue as to how a lot of things work here, notwithstanding your constant postulations.