I don't suppose you could define your usage of the word "hipster" for me? Because I can't see how it fits with my understanding of the word. It looks to me like you're just using it as a generic insult meaning "people who like what I don't like".
That's also why it's a pretty jerk thing to call someone on the internet. Hipster-slingers: you have no frickin idea why people like the things they like. But try assuming it's because they actually like them. It makes the conversation a lot more fun.
I guess I just got confused as I would never use the term that way myself -- as you say, "you have no idea why people like the things they like".
As such, if I were to say "hipster", I'd be referring to the subculture - the skinny-jeans/chunky-glasses/retro-t-shirt/coffee-shop crowd. Being a trait I can actually consistently identify in a person, rather than a trait I can merely assert the presence of without evidence.
I only visualize the people with their crappy and expensive earplugs and ipod telling how much they love music. And they seems to ignore how much their sound is distorded.
Hispters love the words and attitude and despise the knowledge. That's my definition.