Shock:
As said above, it's a POCO (PSE&G/JCP&L) requirement; not NEC
Years back, it was 'common' to install meters inside (basement/garage). IMHO, one of the reasons is efficiency in reading the meters; think of the time saved!
Now, readings by infrared remote, and over data lines, and wireless are becoming common.
PSE&G green book is the place for their specs, and First Energy (JCP&L) website for theirs.
John
