Well you did say "hypothetical", but droping the Melbourne would find the quickest way to extinction, and would be a most thoughtless act. We would lose $$$$$$$. Melbourne is our name, we would lose all our identity, and all we have stood for. We are the pioneers of the game, the birth place. We have won 12 Premierships as Melbourne.
As Titan Uranus has already pointed out, without Melbourne we are nothing.
You ask how we would lose money? If Melbourne sold our naming rights we would lose members big time. Members equates to finance.