It was added by a remote AMZL mapper.   Local convention is that shared driveways are like driveways, in that they are not wide and the public is not welcome.  Plain service has more of a "usable road" kind of connotation.   And, local tax parcel data shows this as not a legal road, but merely pavement over lots.

I did adjust it, after confirming that it wasn't entered by another local.   (I was passengering by earlier and could only cope with a note.)