In addition to what Tom says above, it's possible that they feel that (1) there's already enough wine to taste, (2) the wine has been recently bottled and they don't want to open it, (3) the wine is intended mostly for consumption by the vigneron and friends or at least is not for the export market for the most part, (4) readers of specialized wine publications are interested only in "fine wine" (i.e., Pinot Noir and Chardonnay),* etc.
* I've been told by some vignerons that at least one of my colleagues (who is quite well-known) will not deign to taste anything but premier and grand cru, and I also know of individuals guided by importers who take the same position.