[quote]There are almost an infinite number of ways to structure a maze[/quote]
Not really. Consider you're limited by corridor width and overlap rules of some kind. Also, certain maps do not make for a playable game experience (routes of escape and choke points are things to consider). In addition, maps in games like this tend to exhibit some sort of symmetry which further limits the number of maps.
On topic, do developers really have a copyright (or some other claim of ownership) to maze layouts? That seems far-fetched.