Chicago got him over Anaheim/San Jose because no one on the East Coast(Highest population density) + (Midwest) is even up to watch West Coast games(The NHL is a business and you want the highest viewership you can get to help/benefit the sport.
Look at Connor McDavid. I'm from Chicago and I can't stay up until 9:30 to watch a game all the way through. Youngsters? No. They have school the next day.
He didn't go to the Jackets because Chicago > Ohio (viewership wise/Stanley Cup History wise/etc.)
Chicago's fans travel well too.
Whoever bet against the Hawks getting him got scammed. It was rigged and always has been.