How anyone can walk up to a stranger, call them names, push them, or hit them, (or murder them) is beyond comprehension. This kind of person must be consumed with so much self-hatred, that the only way to obtain any relief is to spew it onto another who appears unable to fight back. This makes them a coward as well as an abuser.
Thankfully, the vast majority of people feel like you do (and I do!). The small minority that are psychopaths, mentally deranged people just show up in the news more, making it look like they are a norm. They are not.