I recently watched a Ted Talk by Christine Porath on why being respectful to coworkers is good for business.
A study on the effects of incivility found that it made people less motivated: 66% cut back work efforts, 80% lost time worrying about what happened, and 12% left their jobs. Incivility is a bug, and it's contagious.
If you have people in your company who are not treating others well, get them out of there as quickly as you can. Thanking people, sharing credit, listening attentively, and smiling will win the day.