Well, for the singing, you can get involved in an ensemble at that church. A church with a good choir usually also has a talent pool of folks who also enjoy getting up and singing once every few months for an offertory, as an ensemble (think “quartet”).
However, I don’t see any way you can just “dabble” in a church choir, because you have to be there for rehearsals; you can’t expect to just show up on Sunday morning and sight-read the anthem. That’s not fair to the others who did spend the time in rehearsal.
But you could certainly explain to the choir director that your “personal schedule” meant that you couldn’t be there for every single Sunday morning, and you could agree with him that you would only show up for those Sunday mornings when you had attended the previous rehearsal. All church choirs everywhere have a certain percentage of diehards who never miss a rehearsal, and also certain percentage of people who come and go from week to week–the choir director is used to it. Now, naturally, he’d prefer that all his choir members were hell-or-high-water diehards, but usually he’s realistic enough to know that people don’t all work like that.
As a choir insider, I will tell you that the reason for the instant glomming-on is sheer desperation. We’re chronically short-handed, and anybody who can sing at all is immediately, desperately clutched to our collective bosom, in hopes that they’ll stick around. And one way of doing this is by bestowing “obligation” on you–we give you a choir robe and a folder, tell you enthusiastically how glad we are that you’re joining us, and we subconsciously hope the collective social reinforcement will be enough to bring you back next week, whether it’s because you feel glad at being so quickly assimilated, or guilty at being so desperately needed, “How can I tell them ‘no’, they gave me a robe and everything?” We don’t care–we just want you. 
And as for the horsey folks who expect you to fall in love with their horsies and all things Horsie–just smile politely and go on home when your lesson is over. You’re a paying customer, you’re not required to be in love with them. When you pay for a meal at a restaurant, the waitstaff may expect you to fall in love with their restaurant, but you can just smile politely and go on home.
Go ahead and volunteer at the cat shelter for as much time as you personally care to put in. From their standpoint, although they may act miffed if you aren’t there Every Single Day from sunup to sundown, again, you have to just smile politely and go on home when you’re ready. But from a sensible person’s standpoint, any help is better than none.
What are some of the other activities that you’d like to do? Just about any hobby I can think of doesn’t require any particular commitment from members to show up for meetings–the astronomy club doesn’t really care whether you’re there for a stargazing party, the knitting club doesn’t need you there, etc. The only hobbies that you can’t really “dabble” in are performance-type things, where they really do need you to make a commitment to be there.
Other than that, I got nuttin.
Happy Monday, everyone!
It’s LOUD, dammit!
