I think this selection makes sense.
Sure it would be nice to have in the US again but it is such a drain on the local economy. Montreal is still in debt from 1968!
Plus I was in Chicago years ago when princess Diana came through. The city basically shut down. You could not travel (drive) a few blocks in less than an hour - really. A Chicago Olympics would be gridlock.
Tokyo didn't need it. Spain has had Barcelona recently but there has never been an Olympics on the continent of South America. That's crazy!
Rio is supposedly very corrupt (like Chicago is not?) but Beijing pulled it off and I am sure they will too.