UK departing passengers' passports are only checked when boarding the plane, and at check-in if you don't use the machine. There's no passport control as such -- it was removed years ago.
If, like me, you use an e-ticket whenever it's available, the only person who sees your passport on departure is the agent who glances at it at the gate.
The crew I saw in CDG were in full uniform and included a captain and second officer. I couldn't see any dedicated channel for them.