It's a long show. It's possible to miss that the show ended and an EP has started. I've spent 15 minutes before not realizing I was listening to an ad. Not saying they're all ads, but some are just really long ads. Then again, maybe tacking an ad to the end of the podcast that tricks a lot of people into thinking they're still listening to the show is pretty brilliant and deserves extra kudos.
The one about the CCrane Headphones was such an advert

That didn't stop me listening the entire interview though lol, although I doubt there is any cans on the market that could beat the value for money of my Sony MDR-XB700 (perhaps maybe V-Moda Crossfade LP?).
Anyway, I digress, the best Edgington Post episode was the one where Mark debated that guy who wouldn't shut up about the immorality of voting. Mark was completely right on this issue in my view, but his opponent wouldn't give up.