"Camera club competitions" sounds like older people get together. I see them posting over processed images on-line.
Saldago book with over processed penguins might be inspiring for them and over processed images on f and i with hundreds of likes as well.

There is some truth to that about older folks coming in but a lot of the better clubs have regular classes on the basics for beginners, host guest speakers, and organize interesting field trips. There can be a pretty diverse demographic.
I did some research on the local club; they seem to occasionally have an interesting speaker. A photo of the group didn’t show a single member younger than I am (60’s).

