When I was about four, I was riding in the car with my mother. She had a big cup of soda-pop from some fast food resteraunt, and she picked it up and took a sip at the stoplight. I was horrified, and made that clear. After all, I was pretty much certain that there was something very wrong with "drinking and driving."
She, of course, explained what that phrase actually meant.
A childhood belief about cars

you weren't the only one
80 of you believed this
- I used to belive that it was Illeagal to drink ANY beverage while driving, not just alcohol.— Emma*
- I used to think that the dangers of drinking and driving included soda, juice, milk, or water.— Rick
- Don't drink and drive! Literally. I would fuss at the driver if they had so much as a coke in their hand.
— Élistariel