It’s a widely held belief around these parts that sneakers on a wire have to do with marking the boundaries of gang territory or signifying the presence or availability of certain drugs.
sneakers on a wire
A pair of sneakers appeared the other day on a wire crossing 27th Street, about a block below Lakeshore. Do you see this kind of thing where you live? Anyone know the history or anything else about this odd activity?
27th Street 
Im with East Texas Red on this one, I think he nailed it. Since you have a couple of hobo shelters in the back yard, one furnished with a chair conveniently placed on the roof and marked with a big red ‘M’ clearly the sneakers are there to alert the brotherhood that this is a hobo friendly house. Two good ways to tell for sure. The first would be to leave a canjo in one of them and then listen for railroad tunes coming from the backyard late late at night. The other way is of course to just watch for remnants of a campfire in the back yard.
I’ll check for campfires for sure, and empty bottles of cheap whiskey.
Just to add to the urban mythology … I heard they were a gang thing, too; a dead person’s shoes are hung on a wire as a memorial …
There are whole groups on flickr dedicated to pictures of shoes on wires.
I believe you have hobos…using the shoes on the wire hobo code to tell other hobos where they can get a good nights sleep without being rousted by the railroad bulls…
I have first hand experience with shoe tossing. My daughter came home from school one day after throwing her shoes around on the way home…our friend Paul and I had to drive her back to the site of the incident, climb on his car and pull them down.
I believe with a lot of kids this show tossing begins as an innocent boredom activity. Shoes get stuck,
However it began with soldiers getting released from war or service…they would throw their combat boots up on wires as a “good riddance” kind of thing.
Gang territory is an urban myth.
Shoe tossing is also a purposeful game for kids on way home from school too. The only “gang” is the public school system.