The US already has a ton of NFL and college football stadiums that would be perfect for the WC that they wouldn't have to build a bunch of extra stadiums just for the heck of it.
Just a list off the top of my head where they can play games.
Cowboys Stadium- Arlington, Texas
Soldier Field- Chicago, Illinois
Ohio Stadium- Columbus, Ohio
Michigan Stadium- Ann Arbor, Michigan
Los Angeles Coliseum- Los Angeles, California
Levi's Stadium- Santa Clara, California
Prudential Center- East Rutherford, New Jersey
Gillette Stadium- Foxboro, Massachusetts
CenturyLink Field- Seattle, Washington
Heinz Field- Pittsburgh, Pennsylvania
FedExField- Landover, Maryland
Sun Life Stadium- Miami, Florida