I will not defend over-pricing of wines but cost is not and cannot be a stand-alone factor as it is inseparable from the quality of the wine and the reputation of the winery, both of which are major factors in the price that can be demanded. The questions that must be asked relate to what percentage of profit are being made, not always by the winery itself but by the importer, the distributor and the store.
Another part of the issue is indeed whether a winery can produce wines that will compete well pricewise. And, of course, the perception of the potential buying audience - whether, for example, a truly fine Israeli wine is worth the same as an equally fine Bordeaux or Tuscan wine. And, to add to that, as you point out, the question especially perhaps in the case of kosher wines, of how valued those wines are in comparison to other both less and more expensive kosher wines from other countries. No-one, for example, has ever accused the better kosher wines of Bordeaux of being cheap.
It is, for example, quite apparent that from an economic position, boutique wineries are not set up in order to produce lower or even moderately priced wines. On the other hand, large wineries can do so, but that primarily in their popular or entry level series. Here the question is partly related to whether those entry level wines can compete in quality at say a $5.00-7.00 level with similar wines from other countries.
Ah...if only I were an economist. Then I might actually understand some of this.....All of which does, however, go a long way in explaining why the issue of "value for money" is a very subjective issue.