Each night, the Werewolf works hard to put food on the table. It's not his fault the Villagers are so delicious. Any Villagers with special fancy pants roles also do their special fancy pants thing at night.
Morning comes and the Villagers find the leftovers of last night's feast and decided that they would be offended by such a tiny matter.
As the bloodthirsty barbarians that humans are, they decide that the best way to deal with it is to argue among themselves and start a vote for lynching someone they think is the poor Werewolf.
If they managed to lynch the Werewolf, they win and should be reported to animal and human rights groups. If they fail, the Werewolf gets to eat for one more night. At least until all the Villagers are dead and the Werewolf wins a free trip to another buffet. Village, I mean.
Night comes and... well, you get the idea.
Whether you are a villager or a werewolf, you still have a role to play. While your objective remains the same as your team's, you do get access to some sweet skills.
You villagers have it easy. Find, bully, and kill the poor, innocent werewolf before your village's population drops to 0.
Seer - Ah, yes, a human with "psychic" powers. A charlatan, if I've ever seen one. You are a nosy person who violates other people's privacy just to see what their role is.
Healer - You are a surgeon, a herbalist, a priest or whatever you choose to be today. Loiter around in people's houses on the off chance that they get attacked so you can save them with your hard earned PhD.
Basic Villager - You are definitely someone. Maybe not so important, but certainly a healthy meal or a part of the voting masses. Toil away during the day and give yourself a proper snooze during the night.
The Werewolves have it tough. Instead of killing one defenseless werewolf, they have to kill an entire village just so they won't starve to death.
Werewolf - A generic werewolf, working hard to make ends meet. Stalk the village streets at night in search of juicy prey to feast on. But be careful, lest the villagers decide to kill you for being different.