phrase used widely by teenagers and young adults in the mid 90s as it was made popular by the comedy geniuses Stew Lee & Richard Herring.
they used it mostly in the second series of their hit tv & radio show 'Fist of Fun'.
It means basically to want everything, if you want the moon on a stick then you want everything, including things you can't have.
Rich: you wanted the moon on a stick...well look! i went up and got it for you!

Stew: but i don't want it!
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A Styrofoam sphere that your idiot science teacher sticks a pencil through so that you can twirl around a light bulb and simulate the Moon's phases
"Hold your moon on a stick and slowly turn around, watching the shadow on the moon. This is what we see of the Moon at different times of the month."
by Fix It! April 12, 2018
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