I would feel really tempted to get the lambo, but you are right. Receiving the prize in btc is much simpler and more profitable.
Vehicles lose value as the time goes by and they get damaged and worn, moreover you have to take care of it very well storing in a safe place (some people don't have a garage), you also have to pay annual taxes to your government over your vehicle and the more luxurious it is, the more expensive the tax is going to be. I don't know if importation taxes have to be paid by the winner as well, but if so it is another cons when picking the lambo.
But I can't deny I would love to drive this lambo around and visit different cities with this amazing vehicle.
You are absolutely right. Even I would choose the BTC instead if I were as lucky as him/her.
Current price of BTC is very low which gives us an advantage of getting more BTC.
If the winner is not into cars much then BTC is the obvious choice.
Cars are a liability whereas BTC is an asset. Maintenance of cars takes up a lot of amount as well.
Holding the BTC for the next bull run will give enough profits to buy a new lambo while still holding few BTC from the winning amount.