In the 1920s partying was a big part in living. Liquor did not make things better for the characters in The Great Gatsby but only made them worse. It brought out affairs and violence that was not needed.
At the beginning of the book it was hard to understand what Gatsby had done to gain all his money. A lot of people thought everything he said was a lie including when he said he went to Oxford college. Later in the book we find out that he only went for a couple months.