The van drivers first mistake was to exit his vehicle. Second mistake was to grab his wallet and pull it out the way he did. Way too fast. I'm sure once the officer saw the gun he immediately realized he could have been shot in that instant.
Don't get out of your vehicle until told. And move slowly. I honestly can't blame the cop for being jumpy.
I'm not going to fault the cop for cuffing the driver. He has to make the situation safe. However once the permit was checked he should have been released. As for his colorful language, no big deal to me.