Here are some facts about people who get arrested for misdemeanor crimes, based upon recent interviews of "nearly 1,000 people charged with misdemeanors in Manhattan, Brooklyn and the Bronx" by a nonprofit group.
Tihomir Petrov, a math professor at Cal State Northridge, has been charged with two misdemeanors for allegedly pissing on a colleague's office door due to some sort of dispute between the two. The school took this dispute very seriously.
Sentences for misdemeanors like smoking weed or sneaking onto the subway usually don't come with any jail time. They don't have to. In NYC, a huge number of misdemeanor arrestees languish in jail for weeks, unable to afford bail.