there's a bike store near me that leaves an air hose outside for public use (Metro LBS on 88th and Lex, NYC peeps).
at about 8:30pm, i'm walking back to my apartment with my girlfriend and a bunch of newly-purchased beer.
i see this kid, early 20's, hipster-type clothes....trying to fill up his tires. he's using the pump (schraeder) on presta valves, and in doing so let all the air out of his tires and was just spraying air.
So i ran up to my apartment and got my little presta adapter, came back down, and found him walking in circles with two flat tires, looking bewildered. i offered my adapter.
now, here's the weird part:
he was riding a time trial/sprint bike that looked a lot like the pic below, except the brand was different (something with a V) and it didn't have aero wheels. definitely full carbon TT bike, no handlebars, etc. we're nowhere near a track - we're in an area of manhattan where the streets are horrible and people generally ride road bikes or hybrids. he had no idea how to use presta valves, and also no concept of the value of the bike - he flipped it over onto the handlebars and plunked it down pretty hard.
so i say, "pretty nice bike, man. all carbon?"
he says "yea, my friend gave it to me after my bike got stolen. he said it's like a $5,000 bike or something"
he filled up the tires, did a little squeeze test, i taught him how to use the presta valves, and he thanked me and went on his way.
here's what his bike looked like: