It's anything but obvious. And your stating that its obvious simply shows your ignorance of the issue.
90% of those stopped are released without so much as a ticket. The vast majority of the remainder are arrested for drug possession. Much of that pot.
There are very few actual gun busts. It's really a tool used to arrest those minorities you profess to be concerned about for drug possession.
Possession of pot is decriminalized in NY. It's essentially a parking ticket except in cases where it's publicly displayed. That's a misdemeanor which can lead to jail time. Cops, to skirt the decriminalization of possession, during stop and frisks often ask kids to empty their pockets and then bust them for public display if the have any pot on them. That happens more than 40,000 times a year in NYC and costs taxpayers about 75 million a year in police overtime, court and incarceration costs.
The police brass ordered the practice stopped. It hasn't. The state legislature is considering decriminalizing public display to end that particular abuse - a bill recently passed the Assembly.
And again its all beside the point since the stop itself is a blatant 4A violation. And I'm betting its upheld on appeal.