This is to me is the key point and was illustrated last night with my Pike Entire Stout. Not worth $10 bucks to me, not by a long shot. I think high price used to be a better signal for high quality. I think that link is broken and its buyer beware now.Leaving aside the question of Pike's beer (for the record, Joe seems to be an outlier in his opinion), this is an interesting point. Does price signal quality? Did it ever? And, if it doesn't, how does the buyer make an informed decision?
My guess is that prices have only ever been a mediocre indication of quality. As some commenters have noted, you can find exceptional, inexpensive beers. (That's one of the reasons some people feel no beer is worth $10 or more.) On the other hand, you can spend a lot of money on a dud. To complicate matters, there's the question of taste. My A+ may be your B-.
I don't think pricing has ever been much guide at signaling quality--in beer or anything else. Some cars are fantastically expensive and break down all the time; others are cheap and reliable. Coffee at Starbucks is expensive and not particularly good. Budweiser is more expensive than Pabst, and only a tiny fraction of people could ever tell the difference.
At the base of it, I think people really trust and like breweries. Since craft brewing started, it has seemed like a communal effort. We connect so closely with the breweries we like that we feel like they are more friend than business. As if there's a social contract between breweries and customers. (I actually share this view.) So, when breweries charge a lot--even if the beer is good--it seems like a slight breach in the contract. As Jared said in comments, "It's all about the hype and money." (I don't share this view.)
There is a great equalizer in the age of the internet, however: information. We no longer have to buy a pig in a poke (or a beer in a dark bottle). We can look at what others are saying first. I've seen a little scorn directed at BeerAdvocate, but I find it pretty reliable. If a beer is getting mixed reviews and it's really expensive, I tend to skip it. Unless Bill or Derek or Angelo says it's tasty, in which case I might try it. I think breweries know this. They can move some product before the word gets out, but not enough to make it worthwhile to release an expensive dud. And information may be exactly the reason some beers are getting so expensive. Because we know certain beers are so well-regarded, they're almost a sure bet to be worth the money.
I've definitely been burned by lackluster beer, but not often. The word on bad ten-dollar beer gets out. Breweries learn this lesson and they don't burn their customers--or they don't and we don't buy their beer. Either way, we have better ways of identifying good beer than price tags.