In NYC, jaywalking is normal. In Santa Monica, you get a ticket.
In some American cities (Chicago), crossing against the light is how muggers and pickpockets tell the tourists apart from the locals.
People who live in downtown Chicago wait for the light because they know that there's very often a car ready to make a left turn right into the crosswalk. Tourists are often from places where, if there is a crosswalk, there's no traffic to worry about.