When you are referee during a match, you take on a role and a character that is required to demonstrate confidence, professionalism and fairness. In doing so, you have to suppress urges to respond to certain things that are said to you by players, coaches and parents.
By responding directly to things said to you during a match, you are demonstrating a willingness to engage in banter or conversation. Some level of dialog is a positive thing in explaining a call or addressing concerns. At some point, if it goes too far, you can feed a fire that can not control or that will diminish your appearance of professionalism and control that is critical for your overall performance.
After 7 years of being a ref, I am very cautious to always be respectful and professional while on the pitch. Yes, there are times when I may crack a joke with players, parents or coaches, but it is in small chunks and only in games where the temperature of the match allows it. Sometimes a little levity is exactly what is needed.
Lastly, one thing I will not tolerate is dissent. I will allow respectful questions by players or coaches over the course of a match, but if it is consistent or in a disrespectful manner, the only thing you will get from me is a warning or a card. I will, ask, tell and then dismiss anyone who can not respect my authority to officiate the game on the pitch.
I always encourage referees to communicate, but trying to be funny can be a quick path to disaster. Be careful and always assume that your comments may not be taken in the way you intended them.