Pack Drive Revisited

Time watching the dogs in Puerto Rico has raised more questions in my mind a about dog behavior.
I can understand why a well fed dog will go out all night to hunt. A pack cruising the neighborhood I get completely.
The dogs are up and down our steep seventy-five foot driveway each time any of the neighbors in their four house spot does anything. Very little escapes them, trust me on that anytime we try to do something with Bonita the others appear.
Like most dogs if you have company these dogs are in the thick of it. Bonita is on the sidelines but amazingly close. The dogs appear very interested in what the people in their spot are doing. This makes so much sense.
When we are here there is really no need for a dog to go off in search of food. I am so well trained I pay off like shaking a piggy bank. Them leaving our porch; what's the motivation there.
Dogs that hang around faithfully each day and seem to be like a pack go off alone to spend time with other dogs. This is different.
The behaviorist question would be, how are they being reinforced for this behavior.  
Stormy goes around pissing on everything, so for the longest time I thought he was territory marking; only he never gets the girl and bigger dogs flood in to do the deed, so what would be the point.
Socially would be my answer, pack drive doesn't seem to factor here if the everyday buds are the pack.
If you see a bunch of stray dogs around, you think they go together. When I began to see dogs I recognized in unusal places, I just thought it odd.
Stormy having a nose to butt two miles down the road does not make sense as a territory confrontation.
Dogs with a spot in a certain distance move about a larger territory without fighting resident males. It is that distance to which I refer to as their territory. Males from outside the territory provoke defense from any male big enough or tough enough to defend his spot.
Blondie visits about a mile away. The last couple of weeks I have seen her in the company of a yellow lab x female among others. At first I thought she walked a mile away from her puppies to get food. Hah, with my kitchen practically next door, I don't think food is the answer. If people feed, there is already a dog in that spot. Today there she was again standing with the yellow lab female.
From almost a mile away she was on my carport when I got out of the car. The girl is fast.  
When two dogs would be gone at the same time, it was reasonable to think they went together, then I noticed them coming back alone. This was interesting to me that the pack didn't return together. I began to notice them leaving separately, which seems somehow unwild dog or wolf like. That's more coyote like except for the visiting other dogs part. 
By learning more about dog behavior when they are not under our control, perhaps it will help me improve our relations with our best friends. Aside from that I find the extent of their travels interesting. I hope you do as well.