I'm a musician, avocationally. I have a pair of Etymotics earplugs that have much flatter frequency response than the foam ones. (Well relatively. Most frequency response graphs of things one puts in or over ones ears don't really look all that "flat." <http://www.etymotic.com/er20.html> No, I don't work for them or know them.) I wear these as a means to control volume in situations where I wouldn't otherwise be able to, but still need to hear things clearly, and they work. As a result, I've had occasion to answer questions about them in public places like conferences in the Bay Area, and I've noted a few condescending and smarmy responses, as well as a "I don't know what that is."
(EDIT: Seems like you're pattern-matching me a bit, based on "stuff you saw on the Internet." However very big changes in frequency response can make big, measurable and predictable differences, even in how well one can understand speech. I've had occasion to undo naive sound-person's adjustments to bring out bass and treble, but as most speech information is carried in the "midrange" frequencies, this makes announcers less comprehensible.)
(Fellow Etymotic user here)
I used to be able to hang out with nerds and I could reasonably assume that no one around would be so scientifically illiterate as to believe that a person thrown out an airlock would freeze solid in two seconds flat. Everyone would know what "frequency response" was and be able to apply the concept. Now, a lot of "nerds" will just pattern match that as an "audio-woo" word and shut their brains off, yet you can ask them about the Fourier Transforms they studied as an undergrad. It's like we're the version of Brasil Richard Feynman visited. <http://v.cx/2010/04/feynman-brazil-education> Most importantly, I could hang out with "nerds" and assume that the vast majority of those around actually knew how to think and apply logic and actually discuss things with people they didn't agree with. Somehow, we've arrived at a state where most people tell themselves they're thinking, but they're actually just parrotting their friends after crudely pattern-matching the conversation. How can I tell? Because it's now very difficult to agree (yes, agree) ideologically with someone but point out they've arrived at their conclusions erroneously. Almost no one actually listens to and really examines facts and logic. They just determine if it vaguely sounds "truthy" in a way that aligns with their politics.
(Worse still, lots of self-identifying "nerds" will use the above process in discussions involving physics!)