What Graduate Degrees Mean to You
So what is the importance of graduate degrees to you? If you're in a position that you're happy in, getting another degree could likely be more trouble than it's worth: it's a lot of time, money, and effort invested into something that you might not even need. However, many companies have programs through which they will pay at least part of the cost for continuing education that is relevant to your job, so you might not be stuck with the entire cost. Additionally, that cost might be made up by an increase in your pay once the degree is complete.
If you're looking for a new job, or plan to do so in the future, an advanced degree may be helpful...or it might not, depending on what type of position you're interested in. In general, "intellectual"-type positions like to see advanced study, as it shows that you're capable of succeeding at the job. On the other hand, for other types of work, it may actually make it harder to get a job, as the company may believe you to be overqualified and pass over you on the assumption that you'll quit as soon as something better comes along.
The main question, then, is whether you're the type of person who enjoys learning and would be perfectly happy putting in the massive effort required in graduate school. If so, you're more likely to have both success at earning the degree and seeking the type of position that would require it.