Your examples are not typically considered "central authorities".
There are many supermarkets and many independent supermarket companies, not very central. But even then, many do refuse those "authorities" and I wouldn't call those who refuse to shop in supermarkets "stupid".
A single car mechanic is not at all a central authority. Perhaps a dealer is a bit more like one (but not really one), and those who tend to trust central authorities are more likely to be those who would take their car to a dealer instead of independent mechanics. Surely those who don't shouldn't be called "stupid", should they?
Some people trust there electric company, some don't. Some buy their own backup generators, some have UPSes on their PCs, many more at least have surge protectors... maybe they don't trust the central authority? After all, utility companies are one of the most complained about monopolies, particularly because most people are forced to use them even when when they don't "trust" them!
Clearly recommendations play a huge role in the real world, usually a bigger one then central authorities, so why would you think they should not translate well to the computer world? Luckily in the real world, most people can figure out which models they prefer. But in reality, the central authority model really is just a small piece of the web of trust model, wouldn't it be nice to extend that web of trust to smaller entities also?