"It's not hard to spot them if you're looking"
This scares the shit out of the socially awkward or those the article is referring to. When entering a situation where I know almost no one, I always try to comfort myself by repeating things like "not everyone is looking at you" and "you are just like everyone else here".
However often times I take your advice and seek out other seemingly alone people and you're right, they're usually easy to spot .. if you're looking.