I'll Have What He's Having
You see someone doing something so stupid it hurts your brain, and you just say, 'I'll do it too,' because you're too dumb to know better.
My cousin started talking to his pet goldfish. I said, 'I'll have what he's having.' Now I talk to my goldfish and my brain is broken.
My friend started running around the block in his pajamas. I said, 'I'll have what he's having.' Now I run around the block in pajamas and my brain is broken.
My brother started yelling at the moon. I said, 'I'll have what he's having.' Now I yell at the moon and I'm a mess.