I've seen chinese delivery guys riding something along the lines of 52x14's, why? Cause they're moving 12 freaking miles an hour. I can run faster than that. And yea, many of em just get their hands on whatever they can afford. And not all messengers fly around on $7000 carbon bikes at 40mph. 95% of them just barely eek by a meager living, it's the other 5% you hear about.