We are taught to do things the right way and abide by rules and norms when we are at school, because this is usually what guides us to find the right path in the duration and keep us out of trouble. Once you reach adult hood and into the real world, this no longer applies. You then have to learn to be flexible, smart, take shortcuts (even underhanded ones if necessary) to get ahead in life, or just to survive in life in many cases. That's reality. People who can adapt to this sooner have a bigger chances of succeed, while people who don't and still stick their "what they were taught in school and parents as kids" principles will probably be less likely to succeed or as quick to.
The "treat others the way you want to be treated" "always be honest" "always stay true to your word" "always be considerate of others first" "always share". They are nothing more than temporary foundational guiders when you're young.
Enjoy any good things, even the little and menial ones, as you will never know what impending distresses could descend upon you in a moment.