I would think it far more useful if droids had something more akin to MAC addresses.
It would be great for the programmers and the people trying to write communications protocols for them (the droids)... but I guess that it'd be tough trying to come up with some kind of "slang name" for a droid named, say, "00:0F:65:42:E7:23" wouldn't it?
Also, with the current area code system we'd run out of three-digit numbers far before we ran out of galaxies...sigh.