"I have no idea why they would park their car and then walka ways to visit other homes. I figured they were on my street a total of 45 minutes, with at least 15-20 being spent inside their car."
Exactly. You have no ideas. Perhaps one of them received an urgent phone call from in deep trouble. Perhaps they made the appointment with her that she would be at her home in half an hour. Perhaps they decided they would make a couple of return visits before they hurried to her home. Lots of things could take place, but you don't know anything about it, you have no ides. But still you make your assumptions. It's way easier to make assumptions about things we are ignorant.
Shame on me, for being so harsh.