There's also the very significant loss of the home game(s) for one of the teams. In our case, we'll have lost a home stand against our arch rival. Granted, it's just three out of 162, but still. And if you're a NFL fan with a season ticket, you're shit out of luck if your team is the "home" team in London.
And like I said, go crazy with pre season games in Timbuktu for all I care.
I bet Villa fans would not be too thrilled about giving up a home game so the team can fly to Arizona for a regular season match.