People are saying what else do you expect from the SPFL but as Andy and others have pointed out, other sports have done it and let's not forget the Premier League in England had mooted the idea of a "39th game" to be played in some foreign land. So not an idea that's come out of nowhere.
As Steelboy points out, if it's a Dundee home game, they might make a fair bit of money from it, if rules regarding gate receipts are followed...