WHY? Because Porsche wouldn't probably sell many Cayenne S without Tiptronic S in the US.
BTW: the manual isn't available yet for the Cayenne S but it should be available (in the US too as far as I heard) sometimes next year.
I have to look up the Cayenne S pricelist and check if the Tiptronic is an option right now because it is actually the ONLY option.
It sounds strange to ask the price of an option if the car isn't available without that option. Maybe your dealer is willing to part the cost of the Tiptronic to satisfy you as a customer.
BTW: around 3 years ago, with a USD at around 0.75 EUR, Porsche cars were much cheaper in the US than in Germany for example. A lot of Germans were pretty upset about that.
After the USD has grown to 1.10 EUR and more, some Americans were upset that Porsche didn't lower the price tag of their cars because of the low EUR.
This is the advantage/disadvantage of a exchange rate and you can't do much about it. As far as I heard, Porsche needs a USD/EUR exchange rate at around 0.80 EUR not to loose money. So the better exchange rate actually gives them extra money to compensate with a possible lower exchange rate. Its actually not that simple but I tried to simplify it.
Don't worry, be happy...there is NOTHING you can do about it.
Each market has it's own rules. Amen.
To GM Austin: yes, this is the Offroad Design Package as far as I can tell.