Evaluating the value of college majors can be tricky. When you look at the reason for people choosing to take courses, not all of them are thinking, "This will make me the next Stephen King."
"I like poetry" coupled with, "I need to get a college degree," accounts for a large number of people taking creative writing.
Creative writing is as useful as most any other liberal arts degree. Most people with liberal arts don't work in "liberal arts." A large number are managers, business people, people in technical fields. They simply needed the degree to get a job, and "creative writing" is as useful a skill as any.
I think there are factors that artificially deflate the statistics. For one, you get a college degree to get a job. (The majority take the first secure opportunity that comes their way)
Most philosophy majors love philosophy, but never imagine being a professional philosopher. If you get a job, one that required a college degree, you've succeeded. I'd say a creative writing degree is just as good as most degrees.
Now how many people are risk takers? If you know you've got the talent, and the ideas, and you are willing to invest your time in writing, your chances are probably much much better than statistics would make you think.
But the fact is, people go for security and the easiest dollar. Writing is competative, so most people will take the first "sure thing" job they can, and they will write part time.
The last factor is talent. Most people who take psychology will not be psychologists. Most who take sociology will not be sociologists.
If you look at college choices, the first thing people ask is, "What do you like, what would you like too do?"
Well, the reality is most people don't think that far ahead, and they will lean towards majoring in something they have some affinity for. And in that same vein, you can say most psychology, sociology, philosophy, history...etc, majors all wasted their money. (If creative writing is a waste of money)
Nah, they got what they wanted, a college degree. But the vast majority are not working in a related field, only those who pushed further than a degree will generally take you. I can tell you flat out, I would never take advice from 99 percent of the people I took psychology with. They weren't that insightful. Majoring in psychology doesn't make someone a psychologist, though they might assume it does.