Actually, in Latin American countries, you don't get the red hand sign to signify stop. You get a red little man.

Sure, it's idiotic and unevolved, but it's also a cultural difference. I knew someone who'd been here 27 years, from the same country as me, and all she'd learned to say was "hhhhhhhhalllllo" (I'm trying to stress how strong her "H" sound was) and "goomornin."

I rest my case.