If you're looking for it, you'll see a lot of young people sporting Costco slippers in public. At the mall, walking down the street, at the Judo dojo. My generation wore pj pants to school, myself a very active participant, so I don't have much ground to stand on to criticize, but two of my close friends tell me they have what I can slipper standards. They won't wear them out to the bar say, but to the store to grab milk is ok. There didn't seem to be a kilometre distance for these standards, but rather a scale of importance. Wear them on a road trip across the province, but not your ten year reunion in the next town. I wore mine out accidentally, as I was doing laundry, ran out of money on my card, and realized the store down the street to load the money closed in 5 minutes. Of course my laundry, and all the soap is already loaded into the only two machines for my whole building. I made it. Just. Slippers are hard to run full tilt in.