I know where you're coming from. I was playing in a worship group that comprised of a singer/guitarist whom couldn't play anything past CAGED & didn't like anything in E, but she was a good vocalist & a drummer that played the same beat to every song (sounded like the drums to "Be my little baby" from Grease).
As these 2 was older & been "playing" for 30+ years, I was considered the one who knew the least about theory & if I gave any opinions about what a chord or arrangement should be, was told "No, no, no, I'm right, that doesn't sound right! Capo on the 8".
I think some churches have singers who only play a little of an instrument because they "have to" & once they have the basics, that's them set. Younger generations do appear to be breaking this (thank's to tinterweb).