Observations around seatbelt signs

I have noticed on flights in the last few months that people seem to be taking less and less notice of the "Fasten Seatbelts" signs. In fact, on today's flight, no sooner had the pilot warned of rough air ahead and switched on the sign, than people stood up and headed for the restrooms. Even during the chop (pilot-speak for rough air), people were getting up and moving around. Luckily the 'chop' was light or we might have had serious accidents.

In the past, if someone stood up while the seatbelts sign was on, a curt call on the intercom usually reverberated down the cabin, and you did not do that again! Nowadays the flight attendants do not seem to worry, or at least not worry until the plane is bouncing around so much that no one in their right senses wants to stand up.

I guess that it will take an accident, where a wanderer is thrown through the cabin, possibly even injuring other passengers. At that point, the airlines will panic and button everything down so that at the slightest tremor, the light will go on and the fight attendants will rush down the cabin checking to see that everyone is locked down.