One of the hobbies I've been interested in for years is working with stained glass. But it's a very expensive hobby initially - buying all the glass and tools is in itself quite prohibitive - and we've never had enough space in this house to be able to set up a work area for me. So this is the sort of hobby I see being much more feasible and accessible through your concept of a "hobby gym"...a place where I can go (at my own convenience) and use (paying as I go) the glass, tools and workspace, as well as the expertise of others. If such a thing was available here and within my budget, I'd probably pursue that interest.
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When you don't like a thing, change it.
If you can't change it, change the way you think about it.

(Maya Angelou)