Your alternative theory is more complicated than your first one; your first one was also similar to the one I proposed on the previous page.
You mean this?
It's not clear to me at all what the food requirements of zombies are.
Last week there were three zombies setting in church for what could have been the longest time.
I figured something in the recesses of their reptilian brains told the zombies at the FEMA station that that was an important place to go.
Similarly for the zombies sitting in church; I really doubt they were praying.
That's nothing like my first proposal at all. It makes no mention of personal memories coming into play and cites no specific examples like Morgan's wife's attraction to her home. If anything, it's like the second proposal in saying that they're attracted to places humans are likely to go; the one you're now calling more complicated.
Nor do I see how either are particularly complicated, since they simply rely on memories and/or instinct, and the former has been clearly demonstrated in the pilot.