We were KOA and Good Sam but in the end I let them all go because our camping style changed. When kiddo was younger we went to commercial cgs mostly for the 'water parks' or little kid activities.
Now we are state parks/COE/county parks etc. only. We just don't use commercial private cgs anymore.
the discount groups are great if used and it is your type of camping but when we went away from private cgs we dropped all clubs also.
When we did have our clubs and used them, yes there was savings we gained. They did help and they did 'pay' for themselves.