I guess I'm unusual. I pound pretty hard for a good price on a boat, but then pretty much disappear off the dealer's radar except for providing good references if they are worth it.
I negotiated a very long time on my current boat, but they haven't seen me back once except for my initial 10-hr service, which was smooth. I've contacted my sales person a few times, but only to ask how it's going, and shoot the breeze.
Not everyone looking for a good price is high maintenance, but I know many are. And I know exactly the type of customer you're talking about. I had a buddy like that, who would freaking take his car in almost weekly for ANY little thing. A speck of glue on the carpet, anything. Damn that was irritating.