This couldn't be farther from the truth, street photography lives wherever there is human life exists. At its core street photography is the documentation of the beautiful moments that occur in everyday human life. So why would it only be centered in the major cities of the world, life exists outside of those centres.
Even though street photography can take place in smaller centres, it can be a little more frustrating at times and slightly different techniques need to be employed to be successful.
streetogrOFFY mainly occurs in the small 16,000 person village that I live in. I sometimes make trips into much bigger cities to work but the bulk of my training, practice, and images come from this small centre.
Street photography in the bigger cities is something to be treasured. There is so much going on and so many people around, that not only is it easy to blend in as a street photographer, but there are so many different stories being told all at once.
As you move to a smaller location, the population decreases drastically and so too do the amount of stories you see. They are spread out much more, and without the hustle and bustle of the big city, the residents are usually much more aware of their surroundings, specifically someone trying to take their picture.
This is where discreetness is king. I used to used a DSLR when I started out and managed to get some great images but I needed something more. It was too large and often would affect my ability to be the "unseen" photographer and document what I see.
I now work with gear much smaller, quieter and more discreet in order to get closer to the action and get the shots I want.