Years ago some noob came up to me and a buddy in the parking lot at one of our parks and said he was opening a shop called "Fairway to Heaven" and asked what we thought about it.
My buddy didn't say much because he was uneducated and just basically played for fun.
I came out and gave him a whole clusterfuck of reasons as to why it wasn't going to be very profitable. In a town with 3 courses, only about 15-20 people show up for Sunday doubles each weekend. A separate group of about 7-10 people show up to league on Tuesdays.
They get the majority of their discs from tournament winnings. The rest of the town is full of non-chelont(I know I spelled it wrong) disc golfers that might carry 1-3 discs, and not know the difference between a Roc and Boss. They'll probably buy 3-4 discs per year if you're LUCKY.
Unless you go into internet sales, you're really not going to have a ton of income. At least for my area where the disc golf scene isn't too big. On top of that (Internet sales), your prices have to either be super awesome, or you have to have free shipping to bring people to press the *BUY* button. I refuse to pay $17-20 for a single Star disc (shipping included). Which is why I order multiple discs when I order.
Just look at the scene you're trying to make it in. I tried to get a whole dye thing going and I donated WAY more than the business that I got coming back to me. After donating close to 20-25 dyes (New plastic), I maybe got 2 people emailing me asking for something custom.
It got to the point where I only really do it for close friends because it's not worth the effort.
Anyways. That's just my thoughts on it.