Your case is more clear cut because that is a glitch in the website. It seems that in this case Doordash is offering a promotion. Calling that fraud would be like calling taking advantage of reward points fraud.
Of course, no one would order it. But in this situation, an aggregator could offer it and the restaurant owner could take advantage of that.
It smells like fraud, except that every individual step seems legitimate (albeit weird). I'm pretty sure you're allowed to charge ridiculous prices for common goods if you so choose...
"I want a supreme pizza, hold the pepperoni, sausage, peppers, onions, olives, sauce, and cheese".