Crocs
This shoe is so well known for comfort that we don't even have to hype it. No, really. We aren't going to do anything. All you've gotta do is go ask a doctor or a nurse or a waiter or a retail person what shoe they'd most like to wear while they're on their feet all day, and what are they gonna say? It's probably going to be "Crocs!" Or maybe "Hey, I'm working here, leave me alone."