Utah has had the following out of conference teams in SLC in the past 100 years (your time frame):
Arizona
ASU
Boise
California
Houston (back when they were in the SWC)
Indiana
Iowa State
Kansas
Louisville
North Carolina
Oklahoma State
Oregon
Oregon State
Pittsburgh
Southern California (admittedly, this was in 1917, so probably not fair to count it, but you picked 100 years)
Stanford
Texas A&M
UCLA
Washington State
So it's not all of the best teams in the entire world coming to SLC, but it's not a bad list. It's certainly more than "Pitt and UCLA".