why does Nick say Gatsby's house looks like the World's Fair in The Great Gatsby chapter 5?

Nick compares the house to the Worlds Fair because it is all lit up, full of people, and has the "crazy" atmosphere of a fair. This Gatsby's big party to impress Daisy. He's finally gotten her to come to a party and he wants to show off all the people he attracts to his parties, how much money he can spend on them and thereby showing her how important he is. He goes so over the top that Nick says it looks like the Worlds Fair because it is so huge (the Worlds Fair was a HUGE event back in the day).