(Historical Dictionary of American Slang, A-G)
gate-crasher n. a forward or undesirable person who attends or enters a sporting event, social function, or commercial entertainment without a ticket of admission, invitation, etc. Now S. E.
1921 T.A. Dorgan, in Zwilling TAD Lexicon 39: The world's champion "gate crasher"...came to grief in trying to "make" the gate at the Vernon arena last night.
crasher n. an undesirable person who makes his or her way into a party without invitation. Now colloq. Cf. GATE-CRASHER.
1922 in DN V 147: Crasher - anyone who goes to parties uninvited.
crash v. 1.a. to force one's way into; (hence) to enter (a party, dance, sporting event, social group) uninvited, without arequired ticket, or the like. Also absol.
1921 Variety (Dec. 30) 4: I want to crash in around here, for makin' good in Denver don't mean a thing.
31 May 1919, Atlanta Constitution, "Two and Three: Putting the Next One Over" by Bugs Baer, pg. 14, col. 4:
Had no trouble crashing the gate, as the doorkeeper thought he was a new kind of turtle.
8 January 1920, Atlanta Constitution, "Bits of New York Life" by O. O McIntyre, pg. 8:
Along Broadway they are known as Gate Crashers. A Gate Crasher is a citizen whose one aim in life is to get into some sort of entertainment for nothing. He is generally a soft-collared, soft-hatted, soft-mannered fellow, who goes about other people's business in a way so delicate that makes other people think the business does not belong to them, after all. They fawn over journalists and call David Belasco "Dave" - behind his back, of course.