freeport,
Without know what you do for a living now, I would still say that a Master's Degree can never hurt anyone's resume.
You may be happy with your current job, but the economy can change and your company may decide to downsize or have a dramatic downturn in business? You might even be injured in an accident an can no longer do your current job. What's the harm in having a backup plan. A Master's Degree may not seem significant now, but it could be much more valuable in the future even if the Degree is in the same career field or something completely different.
You may be young and strong now but life happens and your youth will fade and you may see a day come when you are not up to doing the same job, or you want advancement and more pay. A Master's Degree opens a lot of door, especially if you get your degree in field that can easily transport those skills to other fields. Business, Finance, IT, Networking, Communications are fields that continue to be adaptable to all businesses even if you have a physical disability.
Do it now while you still have the energy...it gets much harder as you get older.
...Rich