I usually try to arrive early so I don't have to worry about it. Since I am generally up fairly late it doesn't bother me at all when someone arrives late. At times it can even provide a little entertainment.
The noisiest part is usually the arrival and getting the TT in just the right spot. In most cases leveling is not too tough. Unhooking can be done quickly and without much noise. Dropping stabilizers only takes a few minutes and can also be done quietly. Plugging an electrical cord in and hooking a water hose up are fairly simple and can easily be done without disturbing anyone.
Not everyone is able to get away early so as to arrive at the campground before sundown. I understand that and certainly don't fault them for it as long as they are courteous and respectful of others. Even for those who can get away and have the best of plans, things can happen such as a flat tire or mechanical problem that throw the entire schedule off. As far as I'm concerned if late arrivals bother someone that much then they probably should reconsider where they are camping. Campgrounds might not be the best place for them.