I can only talk about this for myself. But I think I tend to look at this differently than a lot of people. 'Hobby', to me, means something I do that (a) isn't

I can only talk about this for myself. But I think I tend to look at this differently than a lot of people. 'Hobby', to me, means something I do that (a) isn't my main source of income, and (b) is done for primarily because I enjoy it. (I think some people feel that it should involve skill building of some sort, but I don't think that's a requirement.) So not making it a business is sort of definitional to me. But, things cost money. So I do sometimes make things for other people for payment. But I absolutely will not treat it "like a business" - you are not my customer, you're a peer exploring this stuff with me, and the best way to become an ex-peer is to expect "customer service". Which results in me being very selective about doing so - a lot of people just don't seem to understand that mode of interaction. I am exploring commercializing something I'm working on. But that is no longer a hobby - writing a business plan and chatting up people for instrumental reasons can be rewarding, but not something I do for fun.