This topic has been discussed here at CPF before. Let me see if I can add anything new to all that has been said before.
First, there is a recent study that finds that people DO (as an empirical fact) associate higher price with higher quality, whether there is IN REALITY such an association OR NOT.
Now, this being the good-'ol-US-of-A, land of super-capitalism, companies and marketers know this, and exploit it to the hilt.
If you can sell something for $100, but also manage with good marketing to do it for $500, which would you sell it at? If it flies (ie, if you can get good marketing for less than $500-$100 per unit, which you generally can), you will do it over and over again.
On top of this, there is a group of so-called "positional" goods. These are goods that have value EXACTLY BECAUSE it is difficult for most people to have them. For expensive (even if mass-marketed) goods, this is true by definition.
Hence the "limited edition" coins or whatever, that can be pushed out by a mint or a factory to any number desired by the seller. This also explains why, over time, "limited" editions of anything tend to become unlimited.
Once the limited (ie, high priced) demand is satisfied, then ways are found to flood the market (using surrogate sellers, slightly different brand names or styling, licensing to other countries--which then mysteriously neglect to keep the goods within their borders but come back to the home country, etc.) at a cheaper price. Once this is exhausted, the cycle is repeated in a slightly different good ($2 dollar coins instead of $1).
There are two solutions to this problem: (a) savvy customers, who can tell the quality of the different goods, and who emphasize function instead of bling and resist marketing; and (b), independent organizations (like Consumer Reports) who help the consumer by rigorously testing products for quality and reliability.
As to a good historical counter-example of the "high price equals quality" fallacy, I offer you the British signature car of a couple of decades ago, the Jaguar. If you (or a friend or relative) has even owned one, you know how often it broke down and how costly it was to repair. Yet, it was bought, and at very high prices. QED.