Sometimes we need to be kind to other people. Just saying good morning can make a bright day, and a good smile will make people, including yourself, happy.
I had wondered why Japanese people were polite, but I realized it was hard to curse in their language. Since there are only few letters you can use to cursing, you need to be smart to say sarcasm and think about analogies, and since you need to study to curse, you also need to learn how a person would feel about the words that you made up since you want to say bad things to that person. You learn empathy. But yeah, just being a brat is easier, its easy to know the intelligence of the person your talking to in chat because they use Kanji and a lot of references. *personal opinion
Here‘s Chapter 6 of Itai no wa Iya nanode Bōgyo-Ryoku ni Kyokufuri Shitai to Omoimasu..