The environment under rotors running is potentially disorienting and the rotational threat to life is often invisible.
In most factories with trained and well briefed workers, such a threat to life and limb would be caged and screened if at all practical.
It takes many years of parental guidance to teach kids how to cross a road, yet we expect the public to be fully cognisant of the risk under a helicopter with an unaudited verbal safety brief.
If there was a zero operational cost to shutting down rotors for passenger embarkation, we would do it.....wouldn't we?
Mjb