The world of employment has changed somewhat over the years, fewer post graduates go into a profession that is directly related to their degree.
A degree, in an employers mind will generally mean that a prospective employee will have the ability to work at something over a long period of time and a "degree of" self motivation. And they are acouple of things that on a c.v. will look better than, "tried to be a rock star, but my self absorbed, I'm always right attitude and expensive bass, was unappreciated by the loathsome music industry"
There's more for you at the end of a music degree than you may think.
Music teacher, music therapist, theatre work, cruise ship work, publishing houses, music journalism, production, film/tv scores, sales, etc.
If you're prepared to study for 4 years, and study something you love, and have already demonstrated a level of dedication to by achieving your rock school grade 8, then go for it.
The other thing about music courses, is that they often have "industry people" as lecturers, or the like, coming in for master classes. It's a chance to be noticed, ask questions and rub shoulders with like minded people, who will sharpen you up and give you some direction.
Oh, by the way welcome to the forum. And a bit of advise, don't come back until you've finished your degree. Forums can suck the time you should be practicing and playing out of you.
All the best mate, go for it and don't listen to the naysayers.