What is up with the shoes?

So we were driving and saw this (shoes hanging from a telephone wire)....Of course, my curiosity got the better of me and I took a photo with the phone. Then we saw the movie Freedom Writers and saw this same image again. I wanted to know why and found very little other than this for an answer.

Legend: Old running shoes hanging from trees and power lines are 'gang signs.'

http://www.snopes.com/crime/gangs/sneakers.htm


Across the United States, you'll encounter discarded shoes hanging from wires, poles, and trees. Theories as to what these shoes signify abound, but, contrary to what one hears, there's no one right answer.
Who put the shoes there and why? The list of explanations goes on.

Suggestions include:

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  It's the work of gangs marking the boundaries of their territory.
  


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  Bullies take them off defenseless kids, then sling them up out of reach as the ultimate taunt.
  


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  Gang members create an informal memorial at the spot where a friend lost his life.
  


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  Crack dealers festoon wires to advertise their presence in the neighborhood.
  The shoes increase wire visibility for low-flying aircraft.
  


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  Overly puffed-up boys who have just lost their virginity or otherwise passed a sexual milestone look to signal the event to others.
  


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  Graduating seniors mark this transition in their lives by leaving something of themselves behind; namely, their shoes.
  


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  Kids do it just because it's fun. And besides, what else are you going to do with a worn-out pair of sneakers other than tie the laces together and toss them high?
  


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  In the Southwest exists a similar practice, that of placing old, worn boots upside down on fence posts by the side of a road. Driving along, one passes upturned boot after upturned boot. Some people tell us these boots are a way for a homeowner to indicate if he's gone to town for the day; on his way out, he stops where his driveway meets the road and adjusts the boot so its toe points outwards. When the toe is pointing towards the house, he's telling the world he's home. Others say it's just a boot-on-a-fencepost thing with no more rhyme or reason to it than there is to those sneakers hanging over telephone wires.
  


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  Members of the military have pointed to the practice of pitching an old pair of army boots over the wires when leaving a post as a possible origin for sneaker slinging. According to some, army boot pitching is a ritual performed upon completing basic training, according to others, the boots are tossed when a soldier leaves one post for another, and a final school of thought holds that boot pitching is properly done only when the service itself is being left. The boots are often painted yellow or orange prior to being festooned over a wire.

There's no one definitive answer as to why those shoes hang from telephone wires. Perhaps the answer lies within each of us, shoe-slinger and non-shoe-slinger alike. We are a determinedly decorative society. At Christmas and Halloween, on Easter and the 4th of July, many of us feel compelled to doll up houses, windows, and lawns with all manner of objects and lights. Some call this folk art. Others will tell you it has to do with the human need for self-expression.
Slinging shoes over a power line could be no more than us letting that side of ourselves run riot. Then again, the whole thing could be merely an invented tradition, with people doing it because they see others doing it.

So what do you know or have you heard about this?