Yeah, where have you been. Porsche bought 20% of VW to save VW from a foreign takeover. See, those excessive profits may save the VW Golf GTI
My theory is that they really want a guaranteed buyer of the technology Porsche is spending a billion Euro to develop in the Panamerica sedan. Now they know Audi, Bentley and VW will help with the costs just like with the Cayenne that made them so much money. Profit margins can be pretty high when you have no internal development costs
Seems like smart business, though no passion and they could have spent the money on 2 or 3 seasons of losing in F1 instead