A childhood belief about cars

I used to be so enthusiastic after having had a banana outdoors.
If I passed by a parked car, I ever put the rind carefully in front of one of its tyres, which were pointed towards the open road. It was obvious to me that the car would skid when the driver set off and I always felt sorry I didn't have any other bananas for the rest of the tyres.
Well, I never practised that about buses and trucks for I would have had to eat kilos of bananas in order to make the driver happy. (But I didn't want my tummy to hurt out of overeating.)
My mother gave birth to this flawless belief and she was the person to kill it. Once (years later) she told me she'd been just kidding me.