Because people are sad and angry and just want to let everything out.
OR
They want attention
C.
Since they can't promise that will happen to everyone first, everyone is different so they may not lose fat there first
A. Posting an intentionally hurtful or mean comment on someone's social media and being blocked from that account.
B. Posting photos or videos of yourself doing illegal activities (drinking while underage, doing drugs, etc.). Companies and colleges look at your social media to see what you are really like, which could lead to not being accepted into a college or being kicked out of a sports team.
The first levels of myActivity Pyramid is - everyday activities.