There are other reasons for being nicer and kinder than others.
First, they're looking for an excuse to try to get rid of us at work. People can say cruel things about coworkers around the water cooler but heaven forbid a person with BO says something negative about a person. It will be an excuse to get written up for not being a team player.
Secondly, we have to do our jobs better than anyone else. If they want to get rid of us, they'll find any little error you made and write you up while they let it pass for others.
It's a lot harder for them to try to get rid of a worker with BO when all they have to say about them is that they stink.