I'm not sure I understand what you're saying. You seemed to originally be claiming that there isn't an appreciable aesthetic difference between cheap wine and expensive wine, and that all wine is basically the same when you don't think about price ("When the cost of the wine is unknown to the taster, the differences disappear.")

But the article you provided seems to say that there is a difference between cheap and expensive wine - it's just that most people are not good enough to detect it. I think this is important because it invalidates the claim that "all wine is indistinguishable." There's a difference, it's just hard to detect, and the pros are better at it.

To return to the original point of the thread, though, wine actually is a pretty interesting example that complicates the original poster's point. The more you wine you drink, the more important it is to pay extra. It's not that the expensive stuff isn't better, it's just that you have to care a whole lot to appreciate the difference, so most people actually will be fine just getting relatively cheap wine.