I feel the same way about quilting - this is MY thing and I'm not going to turn it into something I do for other people. It sort of already is about other people, since I usually make a quilt for a specific person, but it's at MY discretion.
Depending on the person asking, I'll usually just say no and explain why; but if I don't think the person will understand (or to save time) I will go the route of quoting an astronomical amount and then suggesting they check etsy if they'd like a custom quilt made for a lot cheaper.
Somehow nobody has taken me up on my offer! It's working!