It's been years and years since I used C# but at the time, ref and out parameters were critical for pinvoke, since pointer arguments are how Win32 functions generally return results.
Oh I'm sure there are valid reasons at the edge to use them, they just make for bad C# code when it's code using entirely the framework; they're overused, usually by programmers who never learned the functional or OO styles and are stuck in the procedural mindset.
