Maybe @NormaJTorres didn't appear at the Gardiner W. Spring Auditorium, but these people did

As I noted previously, there are multiple auditoriums at Chaffey High School in Ontario, the largest of which is the Gardiner W. Spring Auditorium.

If you're a Congressperson who wants to reach out to the people, you hold your event at one of the smaller auditoriums.

But if you're Roy Clark, you head to the Gardiner W. Spring.

Now I didn't see Roy Clark - the only name person I've seen at Chaffey was the (subsequently disgraced) Mike Warnke, and frankly I can't remember if he was at the Spring or the Hill. But according to this page, a number of name performers have appeared at the Gardiner W. Spring auditorium since the 1930s.

Clark himself, a well-known country/bluegrass artist, appeared on April 12, 1991, a little over a month before pianist Victor Borge returned (he had originally appeared in the 1960s).

A few others who have performed at the Gardiner W Spring:

Paul Robeson
The Trapp Family Singers
Marian Anderson
Bob Hope and the Desi Arnaz Orchestra
The Boston Pops Orchestra
Mahalia Jackson (multiple appearances)
The Smothers Brothers (in 1963, before the variety show)
Ricky Skaggs

The complete list (through 1996) is here.

It should be noted, though, that one esteemed performer has not graced the stage of the Spring - me. I have been onstage at the Bridges Auditorium in Claremont.

It should also be noted that the auditorium itself is a Communist plot. Many of the buildings on the Chaffey High School campus today were built during the administration of President Franklin D. Roosevelt, as noted in several sources including the Los Angeles Times:

The 65-acre high school has several historical buildings, including the Gardiner W. Spring Auditorium. Built in the 1930s with help from the Works Progress Administration, the Mission Revival-style auditorium serves as a performing arts center for the community.