What happens when a wine thats one of the good ones in a wine store, is suddenly sold in the biggest supermarket in your country? Does the producer sell his soul to the devil and go from hand harvest to machine harvest, over extract his grapes, and add more water and sugar to counter?

We had the case of Marq de Riscal .

I've seen other Rioja wines go the same route:

Bordon Reserva was in a wine store and still is, but the biggest supermarket in Denmark now sells it. Now, the wine store has crianza and gran reserva too, but the supermarket only has reserva. The price is almost the same (15E), except when the supermarket has sales where it is 5-8E! Wine experts in Denmark say that in supermarkets it is the sale price that is the correct value. I've had examples where that is true (woodbridge, nugan La Brutta), but also some where the normal high price is "just right" (comparing the wine to similar wines in wine stores and the price in the homeland) (e.g. Lamberti Amarone)

So far it is still the same wine as the wine store had and it is my favourite budget Rioja currently. but I guess I should keep an eye out over the next years if it declines rapidly.

Another example:

Campillo Rioja Crianza, Reserva, Gran reserva. The more luxury version of faustino (I do like faustino gran reserva). A wine store here had Crianza 2001, reserva 1998, gran reserva 1994 at prices 20E, 25E, 30E. And they were beautiful . next after LdH these were the best rioja available here. Even the crianza was better than faustino gran reserva. ( and in verticals within the same brand I normally like GR best then R and C - and not joven at all. fasutino I only like the GR).

The supermarket has a "reserva selecta (12E)" and a reserva 15E (sometimes on sale for 8E) of new vintages. Actually another wine store had the new vintages too, at around 20E.
These are not even close to the 199x version the first wine store had. I dont know if it is the lack of age - if they will transform magically in 10 years like the cornasses I like do - or if they simply changed production methods?

Lol, seems this pattern happens a lot with rioja, or I just keep an eye out for rioja more than other types of wine