You reminded me of a something that happened during my '91 trip to WDW: the party was 3 of my cousins (all siblings to each other), their mom (my aunt), my mom, my brother and me.
My aunt and my mom were avoiding the thrill rides like crazy. No BTMR, no Splash Mountain, even the teacups were too intimidating for them.
So us kids had to do something. We had already ridden Space Mountain earlier, courtesy The Space Mountain Run, so we know what's inside. We all queue up, convincing the parents to get in line, too. The fact that you can't see the ride outside or even in line helped.
My mom and my aunt hear the people screaming inside the ride, and get scared. My cousin quickly says "oh that's another ride in the building, that's the scary one. We're going on the slow one."
Somehow, when loading the ride, we got split, and the two parents got on, first, while us kids got stuck waiting for the next train. That worked out to our advantage.
When my parents got done with the ride, oh the look on their faces was priceless! It was utter shock and horror! Their knuckles were pure white from choking the handrail the entire time! Their hair turned into styles resembling The Bride of Frankenstein! I'm surprised any of us kids made it home