Honestly, I don't. Well, I'm in Canada and you said "everyone in the USA", but I don't do it here or in the US. In fact, I get pretty ****ed when I see people going 20 mph (or up here kph) over the speed limit. Do I speed occasionally? Sure do, but it's because I missed a speed limit sign and the car's GPS doesn't display the speed limit on that particular road. As soon as I notice, I slow down. Got caught three times so far. Paid the fine twice (wasn't much over) and once the cop (in Texas actually) just gave me a warning.
Edit: But don't get me wrong, this is not a "holier than thou" post. It's just that particular thing, speeding (especially in bad conditions) that gets my blood boiling for some reason. There are plenty of very stupid and unnecessary gov't imposed rules I disagree with and wouldn't judge anyone for not complying with them lol.