It may not be as complicated as that. When we've been taken before, it was because we simply lacked the power or ability to. The means have always been given to us, if we had the choice to go.

[He's learned that Trench doesn't seem to be much different than Deerington, and has decided to approach it as thus.]

Perhaps it's because we are not fanatics of whatever it is they worship that we cannot enter this supposed sacred place.