I'm not saying money isn't a factor, it should be. It's how everyone gets paid. But if they were just about making a profit they could play it at Geelong and hike up the price of tickets.
The MCG is the best option for this game. They'll fill the place, they'll sell a lot of stuff, they'll have more people engaged in the event and football will be better for it.
If they were playing GWS is might be a different story because the numbers might not add up but why wouldn't you use your 100,000 seat stadium if you were a chance of filling it?