The RAF used to be more robust in its responses in the old days. When Freddie Laker tried to poach VC-10 captains for BUA, his recruiters were banned from BN so they continued doing their work in the local pub instead. The RAF still had a trick up its sleeves though, by promoting the subject captains to Sqn Ldrs in order to counter the extra money that Freddie offered.
It worked to a degree, but they still had to suffer routine humiliation when checking in at Route Hotels down the CENTO route. "Are you a real Sqn Ldr or just the aircraft captain, Sir?". "Oh, then you're in the same accommodation as the rest of the crew, Sir".