assume for a second that they have a valid copyright claim; I mean they created it, and, utltimately, it is only of significance to us if we are using their services. i mean who adds a postal code to an envelope they plan to deliver by hand?
how often have you seen postal codes being distributed? every advertisement (print, televeision, radio, etc), contact info page of every website, every form you fill out with personal information...how many instances is that? thousands? more likely millions? Now how many have been sued for publication of copyrighted information?
Now that someone is directly monetizing that information, Canada Post wants to play the copyright right card, but the horse has left the barn. For better or worse, they have to show that they've always vigourously defended their copyrights in the past, otherwise it's fair game like Aspirin or Kleenex. I'm not a fan of that aspect of law, but it is what it is and Canada Post is too late to the copyright game.
Hell, try mailing something by courier and you still need a postal code. That's as direct a competition as you can get; the most immediate example of copyright violation, but I don't think they've ever sued FedEx (Purolator is partially or wholly owned by Canada Post, so I've heard, so maybe they can use postal codes), so going after Geolytica seems a stretch.