Certainly to an extent some proportion of it is. However, these two in question are not the usual apathetic types that you would expect them to be. They are supposedly "educated" people in reasonably well paid jobs. When I have challenged them they have admitted that they weren't taught the simplest of things such as capital cities when at school.
I was married to an American and my ex Brother in Law is a teacher at a school in North Carolina, which isn't the most advanced of states. But from speaking to him, the kids there do get the same sort of grounding in education that the kids here get. So a large proportion of their ignorance comes from the same reason as you give above.