that isn't necessarily true. It depends on what you're looking for. I'm in a big city now and it takes me about 45 minutes to get to nearest wal-mart or target. It takes me a half hour to get to the mall. If you're living in manhattan and get all your groceries, prescriptions, and shopping done at mom and pop shops, then what you posted is true, but if you're living in a commuter city, it can take just as long to get places as it would if you were commuting from a small town. Even in l.a., the closest wal-mart to me was close to an hour away.
Now suburbs, on the other hand, are great! Keep in mind that small town doesn't equal suburb. There are small towns that are 200 miles from anywhere and there are suburbs on the cusp of a big city. The latter is the best place to live -- you have all the big city offerings, but none of the headaches. Plus, retail shops tend to put their stores in the burbs rather than in the city proper so most things are close by.