I suspect they do a lot more thinking.
It could be that they love quiet not because they're rich, but that they're rich because they love quiet.
As I look around me it seems that those who are the loudest and who crave constant stimuli also tend to be the least intelligent. Families I know that are on the dumber end of the scale seem to always have TV's blaring in the background and are constantly trying to talk over each other, jockeying to dominate a conversation. The more intelligent ones tend to have quieter households and more civil conversations among themselves. At least that's what I've noticed.