If it's so easy, why don't more people do it?

At the Capitol, there are metal detectors at every entrance. You have to walk through them to get into the building. There are people who monitor the metal detectors. Whenever I go through a metal detector at the Capitol, I say "Thank you" to the monitor. It's really easy, it only takes a second, and I imagine the monitor appreciates it even though they would have helped me anyway. The thing is, I don't hear very many other people saying thank you. They're in a hurry to get to work or maybe they just don't say it because it is the monitor's job. True, it's not necessary. But isn't it nice? Isn't it good? Isn't it right? One thing it definitely is, is easy. So next time someone helps you, even if it's their job, just say a quick "Thanks".