Because many things was brought from America. For example, how to think, food, fashion and so on. So you would find Japanese Marriage also changes little by little. Finally, I want to questions to everyone read this. In Japan, schoolchildren and high school students have summer vacation for half a Month.
College students have it for two months.
I heard American students have it for three months. In my case, I work part-time job, go a small tour. I think Japanese vacation is very short. So, if I spend this way, summer vacation is over soon. I want to spent it much slowly.