He could have been enjoying the fresh air, taking a walkabout, loads of things. It doesn't matter, he had every right to be in the neighborhood. So far i know of no HOA that insists you sign in the door and never leave it except by car to hustle out of the neighborhood.
He could have (and imo was) scared about leading some unusual person to his house. I would have been. George never spoke out, said NW, gave him a warning,asked what he was doing but just followed him like someone up to no good. The only suspicious character i see is GZ