Why are telemarketers so thick?

As I’ve said before, working from home gives me uncommon insight into the workings of telemarketers, even though I’m an inaugural member of the Do Not Call List. So lately I’ve been scratching my head over the following: For the last few weeks, I’ve been receiving calls from Scholastic, the Democratic National Committee, and some outfit in Ohio—calls I’ve ignored, thanks to caller ID (perhaps the greatest technological advancement since the E-ZPass). Each of these entities has called me more than 15 times—in fact, Scholastic called again while I was posting this—and I’ve never once answered the phone.