Not that it's funny but the expression "spiritually weak" makes me laugh. They are the weak ones. Anyway, unanounced visits irritate me. When it happens I'll meet them at the door (happened again a few days ago, while they were preaching in the area) and not let them in. Don't want to make them feel too welcome. I do feel a little guilty though, it's not very polite, but to me unanounced visits aren't polite either. It's not that hard to pick up a phone, but then you can't pass the time in service.
Witnesses feel they have the right to intrude in your life at anytime. err.. I hate being harrassed
Not just our lives, everybody's lives. Try doing the same with them and see the look on their faces. It might not be a happy one.