yes :D that's true, for me it's mainly I just like linux :D ...
And why Linux and not Mac?
I don't have problem with Windows. Well, file-system's case insensitivity might be the only one in rare cases.
Use what you know the best and feel comfortable yourself with. Professional web developer should use both Windows and Mac at least for testing and understanding user experience, there are also some tools which are available only for Mac/Win.
If after Linux some nice distros are ones like ElementaryOS. I only use MacOS and iOS devices for my development work, for me it's the systems, performance and is the tools that are only available on Mac and iOS devices. Apps like Sequel Pro, Textastic, Transmit, xCode.
Look at what you use for software/tools and what will work best based on that.