Maybe the first instance is the location of the club member, and the second the location of their car!
I used to proof-read BS/ISO/EN standards for technical accuracy and ambiguity. (i.e. idiot-proof them as far as possible)
Here's one from the highway code:
You are allowed to pass on the inside (undertake) on a one-way street.
A motorway is effectively a two one-way streets running side-by-side, so can you undertake on a motorway?
in order to answer your question I must first explain the inner workings of the site..
basically, in order to require the location box be filled in I would have to hack the inner workings of the site, the way I decided to do this was to create a new field called location (we will call this location2 here), which in the same way as the car owned, I can make required on registration. This allowed me to hide the in built location field (location1) as I cant make that required on registration.
in order to put members location on the members map, I get all users whos location2 is different to Location1 and geocode that location to a set of coordinates for the members map and store these coordinates, I then copy the contents of location2 to location1, this then acts as the "already done" marker, if you change your location, location2 and location1 are different therefore the system knows it needs to re-geocode the location.
so now we have all learned about the inner workings of the members map we can see why there are 2 locations, and now I've been told.. I've hidden one from the profile