More Questions

In addition to my earlier post, I have a couple more questions that have came to mind. The first one is how come I never see Korean people eating or drinking anything when they are walking around outside or when they are on the subway. Where I come from, it seems that the majority of people always have some sort of beverage with them, usually a water bottle or a soda, and it is also very common to see people eating while they are walking around or riding the buses. So I find it very strange that I never see that sort of behavior here, especially considering what a bustling and busy city Seoul is. My other question is why there are barely any garbage cans in Korea. I still typically walk around with a beverage here, but once I am finished I always spend  a good chunk of time searching for a recycling bin or a garbage can to dispose of it into. Is one of these two phenomena a result of the other?