Karl,
I don't think this is perceived as such a big problem this side of the pond.
As Paul said, new underground water & gas mains pipes are plastic.
In this area water service pipes from the street have been plastic since the late 1960's, and the water authority has a major mains replacement program in older areas where service pipes are lead & iron.
All gas service pipes have been plastic (yellow polyethylene) underground since over 20 years. Once again Transco (gas distributor) has a mains replacement program in older areas with iron pipes, there have been problems with iron mains fracturing.
This is why our roads are constantly dug up.
Bad connections on the PoCo neutral are probably less common in the UK due to the fact that most of our PME services are run underground in concentric (neutral screened) cables. If I understand correctly, in the US most services are overhead - often using single core conductors - with a slightly higher risk of broken or poor connections, & exposed to the elements.
To finally answer your question, to the best of my knowledge, there has not been any deliberate attempt to insert insulating sections in service pipes to reduce parallel currents.
