Spending $1,400 on a bottle of champagne is crazy enough — but The Game took it one step further in L.A. last night … dumping the bottle’s insanely overpriced contents all over the sidewalk … for no reason.

Game was on his way out of Colony nightclub — holding a gleaming bottle of Ace of Spades champagne — when he decided to empty it out for the crowd’s entertainment … saying, “You know what I call that? Feeding the roaches.”

Good thing, too … because carrying an open container in public is a ticketable offense in L.A.