I think his point was that the article doesn't mention anything about why he was pulled over, just that there was a "license check". If I'm not mistaken (which I usually am), stopping a driver without probable cause is illegal in most (all?) states. I would imagine Hairston was pulled over for a valid reason, but I can see why tinyarch is skeptical.
You are mistaken
North Carolina is known for setting up "license checkpoints". That is, officers are on site at a stop they've "set up" and can ask for license & registration from drivers and look for motor vehicle violations.
So, Hairston wasn't stopped for a reason specific to him (According to the police... is there profiling that goes on even at checkpoints? Sadly, of course).
Was stopping Hairston allowed by law in this case, even though his vehicle didn't do anything to draw attention to it? Probably.
If I'm his defense attorney I'm doing a number of things including taking a look at how the weed, guns and ammunition were found. At checkpoints officers are generally not allowed to 'snoop' - they are to be looking for motor vehicle violations only. So, if you've got a couple of cops out there and one is asking for license & reg, the other one should not be shining a flashlight down on the floor of the car, etc.
However, if you've got a bag of weed in plain sight, or a cop sees you throwing a gun from the window, you've got issuesd.
But.. in this matter you've got the UNC/NCAA concerns.. and legal issues.. and those two are not the same.