You could discourage this behavior by keeping overhead compartments closed when passengers board the plane. As they reach their seats, then they open a compartm

You could discourage this behavior by keeping overhead compartments closed when passengers board the plane. As they reach their seats, then they open a compartment for their bag. Once everyone is seated, staff closes all the compartments. I think the added time/social pressure having to open a compartment would be enough to stop most people who do this.