In our post-9/11 world airlines have quickly turned customer service problems into law enforcement problems. A customer creating a “disturbance” might really be creating a “distraction” for bad people to do bad things. It doesn’t matter how unlikely this is, especially prior to departure while still on the ground. The culture of precaution and ‘not being too careful’ has granted huge deference to the judgments flight crews make in the instant. And it’s allowed prejudice and ego to trump good sense.
How many times have we seen a passenger act concerned with a flight attendant moving their carry on bag in the overhead, and being asked in response, “Are we going to have a problem?”