Two reasons -
A flight crew member should not be getting a pat down without some serious evidence that they may have a prohibited device on their body. I would question the supervisor as to exactly what led to the pat down and take names and badge numbers (calmly of course) and report it to the union security committee.
Our pax should not witness any flight crew member getting felt up. It is a debasing and potentially embarrassing situation.
I understand the TSA has a job to do. Some take it a little too far. A trip through TPA security tests my patience every time. Why that particular station is so bad, I don't know. There are others like it.