Bug or not.
Internet requirement is DRM.
The game, and others with this "bug", should be pulled from the store until a fix is provided

Have you confirmed it hasn't been? Because the only time I've ever had problems playing Shadowrun without net is when my power was also off playing hooky. Lots of things get fixed without press releases.

Sort of. As of today the suggestions provided by ZłyBratBliźniak (Customer Support Representative) :

1. Run as Administrator.
2, Reinstall the game.
3. Install June 2010 DirectX Runtime.
4. Install the latest DirectX web installer.

didn't work. The only suggestion that did work seem to be that I should allow the game access to the internet which doesn't fits with "DRM-FREE. No activation or online connection required to play."

New suggestion provided by Genoan actually work:

Internet connection is not required for this game to work, it is DRM Free.
The issue is with your anti-virus/firewall software, it is blocking he game in a specific way that causes the crash/freeze. When the game launches the Unity engine checks for network adapters, it doesn't try to connect anywhere, just checks if a connection is available, your anti-virus/firewall software receives the query and instead of answering it with a negative it does nothing, leaving the game frozen and waiting for an answer. You can manually disconnect the Internet cable or disable the connection and add the game to the exception/trusted list, it will launch without an Internet connection. I repeat the issue is caused by the way your anti-virus/firewall blocks software, giving it no answer instead of replying that a connection is not available.

So the error was on my firewall software and not the game itself.
I admit I was in the wrong here, sorry about that.

Eh, it was not a transparent obvious problem, so you expect your first four or so guesses to be wrong.

Edit: It occurs to me that we might want this thread stickied, or at least some official 'This is a known issue, this is how you deal with it' thread stickied.

Just encountered the same problem - game shows black window and didn't start. In firewall's log there were records about blocking application connections attempts from IP 127.0.0.1 to IP 127.0.0.1. So I just added a custom rule for the shadowrun.exe process that allows it's connection from Source Address Hostname localhost to Destination Address Hostname localhost and any ports (and still no any other connection besides localhost is allowed). And after that game starts all fine. So it doesn't require any internet connection, but still require some unobvious actions and this application's behavior is a bit weird.