"My whole goal is to make people laugh," Hazo said. "There is so much bad news."
Only the keen-eyed tend to notice his work. Most of his signs blend so seamlessly with real ones that maintenance workers have been cleaning them, mistakenly believing they are city property.
Examples can be found beneath one of the green bicycle route signs in Schuylkill River Park, where he added one with directions to "Adrian's Pet Shop, Famous Steps and Mighty Mick's Boxing Gym" accompanied by a silhouette of Rocky.
Or in Fitler Square, where, poking fun at the plethora of Town Watch signs, he posted a "Warning Smooth Criminal Neighborhood Watch" with Michael Jackson's profile.
At 10th and Pine, he parked a mini-unicycle under a "Uni Lane" sign. And in LOVE Park, he notified visitors to be on the lookout for "Vampire Squirrels."
He estimates he's made about 20 of them so far, with help from a secret manufacturer. Hazo also prefers to remain anonymous, declining to reveal his given name or to be photographed.
"I don't really know what the repercussions are," he said. "It could be illegal."
A spokeswoman for the Streets Department said city ordinances forbid attaching anything to traffic-control poles. Each violation carries potential fines of several hundred dollars.
Even so, Hazo said, "What I do is nondestructive." His signs are bolted through existing holes in the poles or attached with steel bands that can be easily taken down.
The Streets Department has no record of having removed any of them. The signs that have disappeared, Hazo said, appear to have been taken by admirers.
His work, he admits, is derivative. TrustoCorp, a New York street artist (or artists) is one of several predecessors who use signage for social commentary.
But Philadelphia, Hazo said, seems more receptive to young, untested artists. "If you have an idea, it's yours for the taking here," he said.
A few weeks ago, Hazo decided to step up his game.
"Instead of being measured in inches," he said, "this one will be measured in feet."
Starting out Sunday morning, when most hip city dwellers were still staking out tables at cafes, Hazo parked his car (legally), disguised himself in sunglasses and a cap, and walked quickly toward South Street, carrying a big, black plastic garbage bag.
Inside was an enormous mock parking ticket with an exact replica of the dreaded "VIOLATION" along one end. The upper right corner read, "Place Giant Stamp Here Absurdly Large Postage Required Post Office will most likely not deliver this." The address: KID HAZO Street Art Division PO BOX 092013.
His mission? Slip it under the wipers of a parking authority traffic enforcement car.
Knowing the ticket would not last long once he planted it, he took along a photographer to document the prank.
It was after 1 p.m. when they turned onto Market Street and spied their first PPA officer writing a ticket. Figuring the officer must have parked nearby, they combed the area.
Half an hour later, a PPA car drove past, heading south on Fourth Street. Hazo broke into a run, following at an increasing distance until it turned onto Walnut and disappeared.
Getting desperate, he approached the driver of a parked tow truck.
"Hey, so we're artists," Hazo said politely. "Would you mind if we took a picture of the front of the truck?"
The driver looked at him like he was crazy. "Can't," he said. "Not authorized."
At 3 p.m., they drove down to the PPA lot off Columbus Boulevard.
Not a single car parked outside the locked gates.
"Oh my gosh!" Hazo said. "How can we not find one?"
Determined to try one more time before giving it up for the day, he headed back to South Street. And there, at the intersection with Sixth Street, he spotted the car.
"I have him in my sights!" he said, pulling into a loading zone. The PPA officer circled around, coming down the street, looking into Hazo's car. Hazo ducked his head, pretending to be preoccupied. The officer continued walking. As soon as he was out of sight, Hazo slipped out, grabbed the giant ticket, lifted the windshield wiper - and done!
Then he ran.
A crowd gathered instantly, snapping photos.
"That is hilarious!" said Tahira Lewis, a 19-year-old from Northeast Philadelphia who does not drive.
Less than two minutes later, the officer returned.
He paused, puzzled. Then he shrugged, stashed the sign in the backseat, and drove off.
By then, Hazo was already hearing from admirers. One of his fans had witnessed the prank, photographed it, and posted it on Instagram.
"That is golden," read one of the first messages to flood Hazo's smartphone.
"Sweet," he said. "Finally, payoff."