Foridesign, I want you to think about something.
and trust me I'm not doing this to bash you in anyway. I started in this industry about 20 years ago, and only got into it, because I had a friend that needed someone reliable to work with, I didn't know a buttload about printing, but I'm pretty reliable.
ok now to the point, Would you let someone operate on your brain, if they only did it as a hobby?
Would you get into a Airliner if you knew the pilot only did it as a hobby?
Both professions require years of training, for doctors, you're looking at a minimum of 7 years schooling, for pilots, at least 4, then hundreds of hours in additional training.
Becoming a true graphic professional requires no less dedication, some of the larger shops have combined hundreds of years of experience, dozens of years of schooling, and thousands and thousands of hours of practical application. While many in the sign industry don't enjoy the same salary of both above professions, it does NOT mean they are less professional in any way. I wouldn't let a brain surgeon fly my plane either...
A true sign professional not only knows his equipment; printer plotter laminator, cnc, dye sub, etc. They also know marketing trends, have their fingers on the pulse of current marketing trends, have at least a passing knowledge in chemistry, work with dozens of types of software, take care of networking issues, and in many cases are experts in customer relations.
When you think about it from that perspective, perhaps you can see why "Hobby" and "Enthusiast" are words best left for discussions about model plans and trains.
Just my .02