I think some people do. My first foray into commuting consisted of an eighteen mile ride to my college, followed by a 4 mile ride to work. I had got a used bike off Craigslist and took it to a shop to have it repaired (I knew nothing of changing or fixing anything). I think people expect to do all the learning ahead of time and fail to realize part of the fun is learning as you go. By commuting those distances I learned maintenance, what worked and didn't: gearing, backpacks, routes, times - things only YOU will figure out. I feel people think it's impossible because we live in a car centric environment and anything outside of that is hard to really "grasp" without some reassurance on certain things (which is partially what these forums are for!). Any bike can be commuted on and I find it crazy people are willing to spend $1000 on a bike to commute 3 miles, but hey...it's not my money!