If you love the products of the good earth and the talent behind creative minds and hands, it seems to follow that you should be able to appreciate the drive for quality. If you care about nutrition and what you put into your body, and what you feed your family, then quality should be something that you support and promote.
Indifference is fertile ground for mediocrity. It's when you don't care what you're eating, how it tastes - or, by extension, how well a product does its job - that you'll not make a case for excellence. By not making a case for the pursuit of excellence, you're not so much promoting mediocrity, as validating the lowest common denominator. Now, why do that? Indifference can hardly be something to aspire to.
In wine, quality is not simply a function of the grape variety in question. For example, Pinot Noir is very highly regarded - and often regarded so in unqualified terms. However, it is also possible to produce thin, uninteresting wines from it; just as, by contrast, it is possible to produce well pigmented, deeply flavourful, balanced and interesting wines from Marechal Foch. Obviously, the inverse also holds true if a winery overcrops its Foch, but coddles its Pinot.
Therefore, it's not entirely accurate to label some grape varieties as "quality wine grapes" and leave it there. Wine quality is determined not only by climate, soil and grape variety, but also by viticultural practices, stylistic choices and the overall philosophy that a producer pursues. And these things affect all grape varieties.
If a producer has a passion for quality, it will result in a drive for excellence that will likely be reflected across their product line: this is because the "bar" has been set high. Their dry Vidal is very likely to be excellent, just as their Cab Franc or Chardonnay will be excellent. If the bar is set low, then "good enough" becomes the goal. What if better can result from even just a few strategic tweaks? Why not go for better?
The purported relationship between quality and elitism is a false one. One does not have to have elitist pretensions to desire quality goods, or to desire that goods look wholesome, taste good, or in the case of products and services, that they function well. To desire these things means that one spends some time thinking about them, and seeks increased knowledge about them in order to optimize outcome.
If anything, desiring something better is the result of caring.