Shares are often halted for major news. I think it’s meant to protect sellers from situation where many sell with a market order and the price goes near 0. This would result in a wealth transfer from more naive “Main Street” traders to “Wall Street” market makers. Although if the market makers are effective enough, you wouldn’t need the halt at all.

Do people even hold the physical stock titles anymore? There is nothing preventing someone from selling a physical title. Its why I'm weary of a cashless society.

Stocks are not bearer instruments.

Anyway, you are going to sell your paper certificates in the few hours trading is halted? To whom? Your next for neighbor? Someone on the sidewalk?