I know starters and Players assistants are not the most popular people on this board. However, IMHO the starters and the PA's are there for the higher staffers and the owners.
In my experience, the role of the starter is kind of like an air traffic controller. The day starts with a sheet of paper that has the day's tee times. We note how much traffic is on the course. Starting with the first group, we note the cart numbers, whether there are walkers, and how many players. We ask if the group has played the course before, what tees they are considering playing from and, in our case, warn them about the alligators in the lagoons and not to get too emotionally attached to their golf ball if they hit their ball in the water. Good information to relay. And lastly to gently remind them about pace of play. We tell them that we monitor their time when they finish the 9th hole.
The marshall gets the cart information and number of players from the starter. He'll go out on the course and monitor play. He usually has a cooler of water and sand for filling empty sand bottles. Most of the time, if I'm the marshall, I'll ask if they need any water. Usually just this question will gauge whether the group wants to engage or not. None of us are there for confrontation. But inevitably, it happens.
The bottom line is that the golf staff wants to know the pace of play. We provide them that after the turn. We can pretty much see the trouble spots. We also note the time after the 18th hole. It's more for information on the day because there is not much we can do once you finish.
So next time you want to blow off the starter or marshall, it's not personal. They are there doing a job for the golf staff. Hell, I pretty much blow them off myself when I play, but I don't go out of my way to disrespect them.