Private

Speaking to my beloved child (Johnny Rocket, aka Frenchy) and he told me of a time when our hero took to the knife and started betraying people. Frenchy found our protagonist's ID tags on the ground one day and returned them to him. After many thanks and much gratitude, they parted ways. Later in the motor pool, the squad leader needed Frenchy to do something. He called SPC Frenchy over, "Hey, Private Frenchy!". Frenchy immediately corrected him and explained that he's a specialist. The squad leader quickly replied, "Everyone's a private to me out here."

Now, I wonder what that means? I was taught in basic that you call everyone by their rank, so you can't just call everyone a private. Also, "out here"? Does that mean when he's not at the motor pool he calls them something else?