Recently, I was asked why I use Linux by a non-user. My answer is simple: because, I love it! Now, this does not mean that I have a prejudice against those that use Windows or Mac. The truth of the matter is that I am of the opinion that each operating system has its place. I for example, still use Windows for certain games, but ultimately, it is true, that I prefer to use Linux. A more concise answer is that Linux does what I want it to do and when I want it. Control is absolute or can be limited, by choice. There is also a certain joy of being able to call on various program languages with ease and rapidity, that current users of Windows may not have. The Mac at least uses BASH, to a degree, so Mac users can have an understanding of the power of the console, if they choose to. This goes the same for Windows users as well.
Yes, Virginia(http://en.wikipedia.org/wiki/Yes,_Virginia,_there_is_a_Santa_Claus), there is a console inside of the Windows operating system and it is magic. Before the GUI, it was the only way to do things and before that, people use to flip switches too. So, go on Virginia, tell me that doing things by console is as sad as working with switches and I will laugh at you! Now, Virigina may say: we have powerful IDE's that help us develop in other operating systems (including Linux), so why say that you love Linux because of development? I never said that was the only reason. I said that I love Linux because it gets the job done, just as you love Windows because, it gets the job done for you!
For example, I love the fact that I have the power to customize with ease my desktops. I love being able to use tools and commands with great alacrity in a robust CLI. Not everyone loves that, but then again, the users that I have migrated to Linux from Windows, despite the learning curve, find that with a Distro such as Ubuntu or Mint, they get the advantages of having a GUI desktop while the power and simplicity of the Linux CLI is simply an icon press away. That being said, it has been a long relationship for me and the Linux OS and I don't see myself changing my working habits any time soon.
So if you are a Linux user and you are asked, why do you use Linux, I suggest that you give the simplest and most obvious reason and respect the fact that someone may not agree with you. Remember, that in the end, all computers are alike. Ultimately, they use binary to compile the constructs that provide the user interfaces that we all use. We should be thankful for the diversity of Operating Systems in computing and learn to love the very best of each one.