Riddle Me This

I am sure that most of you have heard the question "If 7-11 is opened 24 hours, why are there locks on the door?".
Well, today I was contemplating many things on my eternal bike ride. As I was looking around, I realized that we are very close to one of the largest cities in the world. That being said, as I was looking around, I was not looking at sky scrapers and industrial areas. No, I was looking at palm trees and fields. Mostly rice fields. The fact that there are fields so close to the city is very cool. A person can get the best of both worlds this way.
The thing I could not get over though, was the sight of palm trees. Yes, palm trees.
I have never lived in a place where palm trees grow. I'll admit that the heat and humidity here probably helps them to thrive, but Saitama also has winter. I've been told that it rarely snows here, but that it can get cold ( between25 and 30 F). First of all, that doesn't seem too cold to me since I have experienced winters in Spokane, Chicago, and Boston. I would think that for a palm tree though, that would be too cold. The winters are pretty mild in Seattle, but you don't see palm trees growing there.
I admit, I am strange. I am excited to live in a place with palm trees and I shouldn't question how they grow. I should just be thankful.
...now, if only I could have stopped with the palm trees. (I really did have a lot of time to think while riding my bike). Today we had a visit to one of the junior high schools that one of us will teach at. The English teacher was very kind and showed us around the school.
Many things are the same as in the states, but there are also some differences. For instance, we do not wear outdoor shoes in the school. We wear wabaki. At the entrance, there is a place to change your shoes and many small lockers to leave your shoes (if you have big feet like mine, you leave your shoes in a tidy manner near the lockers). They also have lines painted down the hallways. I imagine this makes changing classes easier on everyone. As I am taking all of this in, I am wondering what the protocol is for a fire drill or an emergency evacuation. I know you exit the building in an orderly fashion, but it would not be a good idea to have hundreds of people waiting to change their shoes before going outside. Wearing slippers outside doesn't seem very sensible either. It is also taboo to wear outdoor shoes inside. When I voiced this concern to my coworkers, they looked at me like I was crazy. Really, I think it's a legitimate concern if I am going to be working in schools everyday in a place that is famous for earthquakes. Also, I like to be prepared. If I am prepared, I can remain calm and help those around me.
So yeah, I like to think about a lot of things. Because of reactions like those I received today, I don't voice my thoughts very often. I usually limit what I say. Even in school, I never felt like I could fully express myself. I am hoping that this blog, combined with my new adventure abroad, will help me be more expressive.
Next question, why are plastic water bottles called "PET" bottles here...?