I have gone out of my way to purchase products that advertise on podcasts: I'm typing this as I eat a lunch flavored with hot sauce from FuegoBox.
I don't know how well most podcasters do from that. You had a wonderfully lucrative target audience; most of what I listen to has a larger market but with less money. I don't know how many Casper mattresses and MeUndies they can possibly buy. The impression I get from the IHeartRadio-branded ones hint that by the time the marketers and support get their cut, it's poverty-level wages.
Again, thanks for the look behind the scenes. That was incredibly informative and very well written.