I don't think it's so much that they don't read as they are incapable of comprehending what they are reading. I read somewhere that most people read on about a 5th to 8th grade level. To be considered fully "literate" you're supposed to be able to read on a 10th grade level, I believe. Most newspapers are written at about a 4th to 5th grade level.

Or at least I read that somewhere at some point and remembered. I kinda believe it though, most people just don't read very well and I've seen examples of people completely missing the point of what looks to be plain written English. I blame the public schools, at least here in the USA, they're pretty dismal.