I know Ares is the god of war and all but in most stories I've read He mostly acts more like a villain instead of a God. Why would anyone worship such a god? In stark contrast Mars was widely worshipped.
Why would someone worship such a god? So he didn't smite you for your insolence. Who are you, a mere mortal, to presume to withhold due rites from a god? Especially one whom you know is willing to do terrible things to you?
I will add that the Homeric Hymn to Ares shows a much more favorable view. Also, you have such myths as that the Areopagus, which was said to be named from the way that the first trial there was Ares's for murder -- Poseidon prosecuted him for killing one of his sons -- and Ares was acquitted on the defense that the son had been trying rape his daughter at the time.
Ares, Greek god of war, being the epitome of the horrors of war, was accompanied by his children Deimos (dread), Phobos (fear) and Eris, not his daughter but the goddess of discord with several parentages disputed. He wore a cape of the skin of men he had killed. He was fickle promising to fight on one side one day and changing his mind the next. He was also mindlessly boastful, cowardly,and a loud whiner when injured by Athena. His appearance represents all the horrors of war and his shadow across the land is a portent of terror, pillage and death. No hero here.