[Jewish-collector]

There are many locations/venues that can't host the National for one reason or another:

Some venues are too small and/or don't have enough hotel rooms
Some venues not convenient to airports
Some venues/cities the union stuff too expensive and/or other legal issues
Some venues charge too much for having events in their building
Some venues/cities are not good baseball and/or sports towns
Some venues don't want it scheduled too far in the future. In other words, the venue wants the National committee to tell them practically in June or July that they want the show in their facility. But the National committee needs a few years in advance. (One of the Baltimore shows replaced Cleveland at the last minute a few years ago)

etc,... etc,... etc,...etc,... etc,... etc,...etc,... etc,... etc,...etc,... etc,...

After all of this analysis, it turns out Chicago and Cleveland are the only cities that don't have any of these issues and this is why they are considering alternating it between these two cities forever.