No, I would definitely not buy a taco for $78. I do not care if the taco spoke seven languages and could drive a car, I would not do it. I dont care if I had $78 Million dollars. There are perfectly good tacos at Taco Bell, and guess what? They dont cost $78.
Not really the point of the question, to be sure, but I just don't like tacos, nor caviar. That's not to say I wouldn't pay $78 for a meal had I the means -- merely not for this one.
This shouldn't prevent others from ordering it, though. As Publius Syrrus put it: everything is worth what it's purchaser will pay for it.
There is no way I would order a taco that is so expensive. I am very cheap and that is expensive for a taco. Food should be more reasonable then $78 for a taco. I like tacos but not that much. Someone is making a huge profit margin on this taco.
As supporter of free and open marketplaces I have no objection to anyone creating and selling a taco priced at $78. Personally there is not thing, no value that could be added to a taco for it to be worth $78 in my opinion. But the value of any given object is what someone is willing to pay for it.
There is really no argument as to weather someone should pay $78 for any one food item. Most nights consist of microwave dinners or going out, but not spending too much. The economy still hasn't rebounded completely yet so it seems quite excessive to ask anyone to pay that much money for one persons meal.