Agreed to a point.
That said, I expect many of us have been far more accommodating to oddballs (for lack of a better word) on the Trail and at shelters than we migh have otherwise been in another environment.
Why? Because after a while those shelters become like home and we adopt a more tolerant attitude because everyone is an oddball, really - or you are just too tired to deal with it. I can think of more than a couple times when a common sense would have had me push on rather than accept the situation as it were.
It is also important to remember, that the mix of people (and numbers of them) changes rather dramatically in the off season-- those times of year where you might actually end up sharing a shelter with just one other person.
This is particularly true outside of the marquis areas along the AT.
Seldom do you see he context of a person's stay in these discussions. Big difference between a Nobo's experience and that af a lagging Southbounder.
You also never see comments that while violence along the trail remains rare (though not as rare as some believe, IMHO), most of it has either happened at a shelter, or (to a lesser extent) followed an interaction between victim and criminal at one. That is a simple fact-- in most cases those rare tragedies did not begin with someone jumping out behind a tree along the pathway but rather at a shelter.
So yes, expect the best-- but be smart. Especially if you are hiking off season in a less popular area either by yourself, or asart of a M/F couple.