* Trains may stop, preventing a literal train wreck.
* People doing delicate tasks (e.g., a surgeon, someone operating heavy machinery, even someone cooking) may lock to a safer position.
* Elevators may stop and open the doors safely, so no one will be stuck inside them.
* Air traffic control may hold take offs and maybe landings.
* All traffic lights going red may slightly reduce car incidents. Seems minor, I admit.
Also, people with little experience (me!) do NOT understand that an earthquake is happening until after the fact. Some blast alert even during the earthquake is very helpful for tourists and even immigrants.