One thing not mentioned in the article, but that I noticed the first time I came up to KC to visit... Porches.
In the deep south, porches are endemic on older homes. One of the best ways to escape the heat of the house was to go out on the porch and cool off. People would walk by, strike up a conversation, and bang. You have new friends- that just so happen to live within walking distance. I've been invited on the porch on more than one occasion... Sit down, have a nice beverage, and talk. I remember one time I was walking down the road with my guitar and a father and son invited me in to jam with them.
I made it up to the midwest and one of the first things I asked my-then girlfriend was "where are all the porches?". Well, there aren't any. People don't spend any time in the front of their house, opting instead to hide themselves in their backyards.
So, want more friends and acquaintances? Get a porch.