I spent a good chunk of time in South and Central America a few years back -- there is a seemingly huge divide between my (a Seattleite) perception of traffic and that of most people in several of the countries I was in.

I would occasionally get stuck on the highway for hours behind accidents, rock slides, etc. and I was one of the only people who seemed remotely bothered by it. Everyone else just kind of sat there as there was nothing they could do about it. I remember asking about it and people just sort of shrugged. Here's a picture I snapped of a flipped semi that caused several hours of backup -- http://i.imgur.com/SEuEj.jpg

The funniest part was how quickly the old ladies with baskets of mangos/frescas could somehow seemingly appear knocking on your car window asking if you wanted anything to eat or drink.

Simple: public transportation sucks and will probably take twice the time to get to your destination. Motorbike: you have no idea how madly people drive down here, and how many motorbikers day each day. Also, it rains (heavily) almost daily from November to April - definitely not fun on a bike