Yeah, I remember Jonathan talking to Clark about that in the Pilot episode. His fear that someone would discover him and...actually I just looked up the script. It says:
Jonathan: Metropolis isn't the cutback, you know. People in the city are always looking to make a quick buck. If they (there's the "they" referrence) find out about you they'll put you in a laboratory and . . .
Clark: . . . "dissect me like a frog." I know, Dad. Believe me, I'm trying my best to be like everybody else here.
Later -- DJ