moon on a stick 

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!

moon on a stick by Lucy-fer in the sky with diamonds January 1, 2005

moon on a stick 

when one wishes to have it all

"would you like anything else? the moon on a stick perhaps?"

moon on a stick by Anonymous September 10, 2003

moon on a stick 

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."

moon on a stick by Fix It! May 25, 2018