"Because little kids wear them. Or...well they do when they're on tv in the cartoons. You can tell someone's a little kid by the beanie propeller, short pants, and giant lollipop."

Mike knows THINGS about THINGS! So long as those THINGS are classic cartoon sight gags.

Between bites Raph adds, "He's thinking he he just dresses up like some kid from way back that he can trick assclown over there into thinking he's eleven."

"THEN!" Mike chimes in, "When he goes and tries to threaten me, Raph..."

"Beats the snot outta him. Which I totally would if he laid a hand on you, but not if it's because you were actin' like a doofus first. That's a beatin' you'd deserve."