Well in that case you get to have the car towed to the parking lot of the tire shop you want to get raped by (since you'll need to pay whatever they are asking for a tire) so it can sit all night and hopefully not get broken into or stolen. Then in the morning they "may" have the tire in stock for a silly price and you can make a trip to the tire shop to pick the car up (via cab or friend). Or, you can have the car towed twice (probably an hour wait each time) - once to your home (so it will be protected and you may find a tire) and then once to the tire shop where you still get to make another trip in a cab or with a friend to pick it up.

No spare with a blow out (or even a tire so badly damaged it won't hold air) is crap. What's the point? So Porsche can save a couple bucks and keep 25 to 50 lbs off the car?