I used to work at a modem company, and one of the technicians told me about a guy who called up with a modem problem. This was a few years ago. The conversation went something like this:

Technician: "Hayes technical support, may I help you?"
Customer: "I got one of these Accura 14.4 modems and I can't get on the Internet."
Technician: "What kind of computer do you have, sir?"
Customer: "You mean you have to have a . . . {click}"

Now, I try to be understanding, but the notion of buying a modem and no computer and expecting to get on the Internet is way out there. It's not just tech support/customer service, though. Go around and ask your non-geek friends whether the sun revolves around the earth or vice versa and I think you will be surprised by the number of wrong answers. People learn what they have to know to get by from day to day, and astronomy, technology, and politics (along with a host of other subjects, for that matter) aren't part of the curriculum.