all three of those stadiums were concepted as NFL stadiums. a true multi-purpose stadium (such as Minneapolis's old Metrodome which was designed for the Vikings, Twins, and Gophers) hasn't been built in decades. A soccer team playing in an NFL stadium isnt close to the same thing...in fact I bet outside of the Sounders, there isn't an MLS team that doesn't want its own soccer-specific stadium, most nfl stadiums are too big. new nfl stadiums are developed with heaps of supporting amenities surrounding the stadium, Soldier Field doesnt have the surrounding area for that unless the city wants to buy the surrounding blocks to make it happen The new "multi-purpose" stadium concept is a venue that is primarily used for football, but has a dome/retractable roof so that it can also host Wrestlemania or the Final Four or the NBA draft or whatever. Teams with fairly new stadiums (or remodels, like Cleveland and Chicago) are now enamored with spending millions on either new stadiums or retrofitting their current stadiums just to host the occasional indoor marquee event. a football stadium that hosts other big ticket events...like every other football stadium built in the last 50 years. I'm nit-picking the term "mulit-purpose" here, but the meaning was meant to describe a stadium that had no specific or primary focus/team/sport. Nobody is building that type of stadium any longer, because they end up sucking at everything.