Kevin all good points and advertising is always a key factor. You see it it at craft shows as well. A show needs to be promoted not only by the people putting the show on but also it helps when vendors themselves promote their appearances. I use to make up cards for where my next show was and left them on the table along with my business card. Putting ads on storefront windows was always a good source of advertising along with the newspaper ads. Some methods of advertising is so simple and free and yes some it does cost money. But the old adage you need to spend money to make money rings through.
But one thing is yes a hobby can become a business if you are willing to put the time and effort into it. You do need the business side of knowledge to go along with the skill set. But this is why people hire others to do that end. I agree with Ray when he said that many times people try to make their hobby into a business and get burned out and that is one of the reasons. Because they have no experience setting up a business and doing the leg work to get it started and it burns before it is established. You did not start out making the money you are now and I bet you questioned yourself about another failed business attempt when you first started. But you stuck with it and being you have some background in business you are making it work. It is not for everyone and many times a family comes into play. You probably have a unique setup where you do not have to feed a family, pay all the bills and a mortgage and provide for college educations and things like that. Because if you did a small business as yours will not get it done. When people say they have a business they more than likely have other incomes or other factors such as kids are on their own and house is paid for and other things. But to take a small hobby such as scrollsawing and knitting and pen turning and make a full time living at it for a long time is probably impossible unless you have other income. Just the way of the world today.
If you had your business set up 25, 30 years ago and there were the etsy and ebay and power of the net around you would easily tripled what you make now even at the money value back then. Those things were not around. It was the craft shows leading the way. Easier to do than today with all the competition from the web. So yes you have to advertise even more so today to stay ahead of your competition.
So make a living at selling crafts as you say can be done but far and few in between. I believe my statement above with family being a key. I too know a husband and wife who gave up their employment to give scrolling a chance at a business and this was at the height of the craft movement and they did well but they were constantly working at it day in and day out. They had to move out of Nj and went to Pennsylvania where things were somewhat cheaper to live but kept the business going. No kids so that helped but could not sustain it as the market and economy started going south. The cry for crafts is not there as it once was. I wish you continued success in this endeavor of yours and hope it stays rewarding for you.