We have a little investor-owned utility out here in California called Pacific Gas & Electric. In more rural service areas, like the Sierra Nevada foothills, they often drop power to a customer-owned pole on the residential property, with a meter base and cutoff box (often a metermain panel) installed on the pole by the property owner.
The metermain is the service point, where the utility drop (or service lateral) neutral and the grounding electrode conductor are bonded. The pole is indeed a built object, in other words, a structure.
We run a three conductor feeder (2 hots & a neutral) to the house and treat the house panel as another "service" as far as system grounding configuration goes. We install a grounding electrode system (a Ufer in the foundation) at the house and bond the neutral and the grounding busses with an MBJ.
This is a major utility, and as far as I can see, it's a Code-compliant installation. I agree that if the phone co were to install their network interface device on the pole that's the point of service, you could have a metallic path between structures, and potential for a fault current on the phone line if a ground fault occurrs and the neutral of the feeder is compromised. This isn't an issue because the phone co runs their drop to the house itself.
Cliff
