Thanks to Brownstoner are in order for posting my "Why are there power lines in East New York?" question as their closing bell on Monday. My curiosity centered around both the lines' existence and the shoes that adorn them. Brownstoner's followers offered some insights, but the first question, at least, remains unanswered.
On the shoe-tossing query, posters were split on the two leading theories, "gang territory markers" and "kids goofing off." Ultimately, I think these two bleed together: kids goof off and throw sneakers over the wires near where they live. Kids are sometimes in gangs. Gangs identify their turf, sneakers on wires become appropriated as "turf markers," and more are thrown up. Meanwhile, some kids down the block mimic them because it looks like fun and they're kids. The point, I suppose, is that gangs and miscreant kids are a pair of groups with a whole lot of overlap.
As for the persistence of power lines in ENY, I don't have an answer. Respondents mentioned that ENY isn't the only Brooklyn neighborhood with power lines, which is true: Red Hook, Gravesend, parts of Canarsie, and parts of Dyker Heights also have their full grid above ground, and lots of other nabes have bits and pieces in the air, such as the telephone lines in backyards in parts of Bed-Stuy. So perhaps my argument that above-ground power lines are "rare in major cities" should be revised to "relatively uncommon in Brooklyn." Still, my interest in the original question remains--why are the lines in East New York above ground? What sorts of factors led to some neighborhoods having subterranean power supplies? There must be a history of this out there somewhere, but I haven't found it yet.
On an unrelated note, the photos above illustrate another interesting feature of ENY--the remarkable continuity of its rowhouses. Street after street is either composed of turn-of-the-century brick numbers like the ones in the first photo, or identical red-bricked ones built (I'm guessing here) in the 1970s. On a sunny day, the uniformity gives the neighborhood an almost suburban feel. As long as I'm asking questions, if anyone has any information on the building of either breed of rowhouse, I'd be curious.