I sleep in a racecar, do you sleep in a racecar
A pathetic attempt to sound tough when you're clearly not. It's like when you're getting beaten up and you just throw out a stupid line because you're too scared to say anything else.
He said it during a fight with his brother and got laughed at.
She used it during a spelling bee and made everyone snicker.
He yelled it when he failed his science test and everyone turned on him.