broken bottles
A young kid asks his dad if he can borrow the car for the night so his dad lets him have the car and tells him to be careful.
About 4 hours later the kid comes home and has 3 flat tires and he is a bit upset. His dad asks what’s wrong so the kid shows his dad the tires. His dad examined the tires and pulled a piece of glass from a beer bottle out of one of them.
The father asked, “Didn’t you see the bottles in the road?” and the kid says, “No, that damn bum had them hidden under his coat!”