Do people who force their kids to listen to tech podcasts in the car really exist :)? And why would you not use headphones if listening to a podcast at work?
I'm a sad, sad man :( Aren't you glad I'm not your dad :)
As for headphones at work, that's what I do. I do know that some like to play stuff for the techs around them, but it's the managers who have a hissy fit if someone drops an f-bomb or a crude joke. Personally I wouldn't want to work at such a place, but there are more oppressive, bureaucratic work environments out there than there are cool places like 37signals.