Play Nice in the Playground

I do not really understand why people do not play nice especially in the same networking group. First of all, if you have an ongoing attitude problem with one person or several people word tends to spread, after all gossip tends to spread more quickly than good news. Also, if you are the playground bully you are just making yourself look unprofessional and people will keep that as a mental note on why not to work with you. My advice? Play nice people.