https://thenewstack.io/ffmpeg-to-google-fund-us-or-stop-sending-bugs/ - the solution is simple. Publish under licenses that corporations hate, but are technically still Open Source. The GNU Affero Public License is my personal favorite.

Then, if Google approaches your volunteer club about dual licensing, you can setup a support contract for moneys if you want to, or, much more fun, show them how gorgeous your middle finger is.