1. Money
This one, guys, is a no brainer. If you do actually master a few of the skills you can start making some money off your hobby. These can range from the easy to the super skilled, starting with selling texture packs and resources all the way up to actually selling a finished game, although I can't express enough just how much work that really is. From a less direct angle the skills you're creating from your hobby are marketable in themselves. Having genuine coding experience makes you a much more attractive job candidate for so many jobs that have even anything IT related in them and shows you are a keen bean. Having a working prototype of your designs that your potential interviewer can play with will make you not only stand out but help you get your ideas across better. And not to mention putting together anything like this shows you have an awful lot of drive. If you're super keen and get together a group of friends you can even go for systems like Steam's GreenLight where for an entrance fee you can submit your projects to be rated by the community, successful projects are sold on steam! This requires your project to be very polished and really is for indi game developers not the casual designer, but this does prove that the sky is the limit.