If I were in charge of something like the city of Munich I would put out a memo that says, "If you talk to a large software vendor then your continued employment is unlikely."
Wow, I would never want to work for you. I mean I love Linux and open source. Heck, don't even have Windows installed on any of my PCs, but to say no proprietary thing ever.... There are really neat things and software packages out there. Sure they cost a fortune, but the Open Source versions are crap in comparison. Then you have to deal with industry standards / common training. This is where Microsoft has traditionally won, but their ribbon interface and Windows 8 threw those advantages out the window.
Here's a few examples. Cad software. There are FOSS versions available, but proprietary versions, like Eagle, are significantly easier to use. Another example is DMX lighting controller software. The Hog 3 PC software sucks and costs a fortune, but it's commonly used and the FOSS versions are unusable for large on the fly modification.
A common retort is to just hire a person to code what is needed. Here's the thing, I can't. First, because I need the software now not two years from now. Second, because in many organizations the equipment budget is handled separately from the labor budget. Good luck trying to shuffle that money around.
With all that said, I'm glad Munich has stayed the course. There's no way this rollout could have been easy, but they did it!