It occurred to me that much gnashing of teeth and rending of shirts could have been spared had the barista said "you aren't going to like anything here." But that would have totally pissed me off 'cuz who was she to judge me?

I wonder how much of the hipster stereotype is due to people saying things like that in a not-necessarily-judgmental way. There are an awful lot of situations that call for saying "you aren't going to like anything here", "you don't care", ... just because they're almost certainly true and they'll save everyone some frustration, but they'll never be taken that way. And maybe it's good that you stop trying to use them with a little experience; sometimes the waffle house waitress really will enjoy hearing about Ramsey theory, sometimes Ned Flanders next door really does want to talk about Christian Death, and sometimes the kiddies really want to be reassured that it's not always just a phase. Still, I don't think it's a coincidence that the people being tarred with the "you probably haven't heard of it" brush grew up with the Internet, where everyone can develop their niche interests as deeply as they want and everyone has been burned by trying to share their enthusiasm only to be met with glazed eyes.