Old Japanese vibe, still in operation !
All Meitetsu trains have music horn, pretty special. You may hear it when riding the μSKY Limited Express from Central Japan International Airport.
spoiler
So powerful that can cover the announcement. I hope the JR lines passengers can still hear what the announcement.
I can't explain what he is doing, but I doubt it is a robbery. As after picking the stuff, there is a brief interaction between them. Maybe he is getting his ticket to board the train.