MacGnG...
i too have considered the possibility that the Giant Hamburger was powered by the meat of some supremely intelligent species of monkey...
but after some (admittedly rather shallow) research into the background of the mysteriously lettuce endowed behemoth, i have discovered that it is just the little games he plays with us mortals that have confused you and i.
like the bizarre mutation experients...
and the baby swapping operation he masterminded...
and his efforts to ´funkafy´ the species...
do not be fooled.
the Giant Hamburger is no monkey...