Thing about the Amish is that they're basically a lot more normal than people think. Some actually aren't pleasant people, are greedy, etc. but no higher a % than the population at large. I guess it varies from community to community but at least in Pennsylvania they don't seem nearly as isolated and closed off as you'd think (one complicating factor is you have a complex spectrum from Old Order Amish all the way up to Mennonites, who wear simple clothes but drive cars, etc.)
Other interesting thing about them is most of them are QUITE wealthy - they usually have the best farmland in a given area, and, obviously, aren't blowing money on a lot of the stuff a typical.
One thing that always struck me funny the last few years passing through Intercourse and Paradise is all the Amish kids tooling around on bright shiny silver Razor scooters.
You are correct that there's every degree of Plain Church group in Lancaster county ~ and if you were a necktie salesman, you'd find somewhere else to set up shop.
Mechanization and automation installed throughout the postal service pretty much banished neckties ~ too dangerous ~ but I remember the day when Lancaster post office was the ONLY one in America where no one ever wore a tie ~ best way to get comfortable at a meeting with those guys was to take off your tie.