Inconsistent Design on Windows Desktop Apps

I can't stand it.

The last examples are Wunderlist and Skitch. Both changed their UI and now they look out of place. This is more remarkable when you're using a dark desktop theme, and those white windows are distracting.

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Why they do this on Windows, with apps clearly designed for OS X?

It's because Microsoft don't even respect their guidelines (Visual Studio 2012, Office 2013)?

What do you think?