Many people don't know how to use a manual camera. That has been for a long time, but before one needed a little bit more involvement, cameras having a more rudimentary automation.
I remember being handed a blackberry by a classmate to take pictures of them. I was struggling with the thing (shutter lag and lack on responsiveness), she said to me: "I see that being a photographer is not your thing!". However, I've never talked about photography with them, neither they do know it's my hobby. Smartphones might be decent for snapping, but quite frustrating!
And from that same person, I handed my digi P&S to another classmate for a group shot. It was a bit badly framed, with some hair cut. "I quite liked the pictures that your camera made, now not so much"
Well, I guess that handing them an unmetered manual camera would be a sweet vengeance.
Back on the topic, I think that presetting the camera and giving general indications is ok for the touristy grab asking. About your friends, perhaps is an opportunity for some teaching/learning.