Mr. Principal:
The traditional marketing chain of small potato producers explains everything. There are 8 intermediaries who have the potatoes produced in the important potato-producing regions of the south, before reaching the final customer, specifically in Santiago.
The small paper farmer sells his production to a buyer who comes to his farm and he sells to a wholesale warehouse in the nearest city and that wholesaler sends the load to Santiago. Once the merchandise arrives at the large commercialization market of the capital, it is sold to the highest bidder, which is awarded by a consignee (all or a lot). Such consignee then sells to a wholesaler and the wholesaler to a retail distributor. Then, that distributor sells the product to small retail businesses (neighborhood stores, stalls at free fairs, minimarket, etc). The last link is the direct sale to the final consumer.
Only in the cities close to the potato producing centers and where the producer-consumer relationship is more direct, do some intermediaries disappear. The chain is shortened and the purchase-sale prices favor both the farmer and the consumer.
Marcelo Moraga A.