crush space
n. The areas in a stadium or other venue that are designed to handle large crowds before and after an event and during intermissions.
Examples
2002
The Civic Theatre's stunning Tay Street facade is on track for an equally impressive interior.

Huge plans have been drafted for a massive $ 11.46 million redevelopment of the theatre which Invercargill Mayor Tim Shadbolt has called the city council's "last big community project." Aside from some strengthening in the 1980s, the theatre has remained unchanged since its 1906 opening…

At the front of house, the scope of work planned includes: Reconfiguration of the Tay Street entrance to increase the crush space in the foyers.
—Cherie Sivignon, “Civic to shed shabby and dated interior,” The Southland Times (New Zealand), July 08, 2002
1999
It is hard to predict whether Torontonians will appreciate the generous amount of "crush space" designed into the Air Canada Centre.
—John Barber, “Ghosts of the Gardens tell tales of glory and disgrace,” The Globe and Mail, February 13, 1999
1981 (earliest)
In January, 1980, when John Sewell was still mayor, Bacque applied to City Council to demolish the auditorium and restaurant, offering to recreate the Round Room at street level if the council would agree to the demise of the auditorium. He was turned down in September by City Council and requested "to lease to a public trust for a nominal sum for a term not less than 30 years, Eaton Auditorium and related crush space, preferably the entire seventh floor."
—Adele Freedman, “Supporters to save the Eaton Auditorium,” The Globe and Mail (Canada), April 04, 1981
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