You are correct that 120V/15A has very little potential for arcing that would be directly dangerous to you, and I've also known an electrician or two who used that method.
But I really wouldn't recommend doing that. There's a wide and complex canyon of consequences between "that little blue arc won't hurt me" and "triggering a fault current will not damage anything, anywhere, either short- or long-term".
But I really wouldn't recommend doing that. There's a wide and complex canyon of consequences between "that little blue arc won't hurt me" and "triggering a fault current will not damage anything, anywhere, either short- or long-term".