The fact that they just show up at your door doing their "field work" sort of conditions you for what's to come.
They think its OK to just impose upon you at any time and that you are supposed to drop what you are doing and attend to them.
After you are in, you are already conditioned to their "impromptu" visits.
I have always thought this is rude!
I was brought up that you "call before you come".
This dropping in any time is, to me, an aspect of inconsideration, arrogance and manipulation. They are more important than any plans you have.
This should be a red flag from the very beginning.
Anyone so easily manipulated is a good candidate for a study. Maybe that's how they peg them.