This isn't "seek out LARPers". This is "how do I distinguish a group of people in the woods running around in camo as LARPers or violent extremists". They found the people first.
Stop and frisk isn't "seek out black people", they found the person first and then identified him as black and that means he is a risk and needs to be stopped and frisked.
I didn't interpret the article as "investigate LARPers to make sure they're not domestic terrorists" so I don't really understand your take. Stop and Frisk has obvious racist origins, but the process starts with you suspecting someone of a crime and using that as a foot in the door. This seems the opposite guidance of "before you spend too much time investigating a group, try to build the case that they're not LARPing". Like the whole preface is that terrorists are trying to evade justice by saying it was all a game. Stop and Frisk wasn't created because people carrying weapons and committing crimes were pretending to be minorities so cops wouldn't be suspicious.
