Connecting the kitchens and the workers leads to eliminating expensive waste. Yay. Predictable incremental revenue streams for restaurants on weekdays are amazing from their perspective. After having customers and data, a couple iterations down the line I think they can probably offer something as compelling to the food customer -- e.g., fixed pricing, which could make this very competitive with business catering. That is almost certainly a 9 figure a year business in NYC alone.
[Edit: Someday, I want to hear the story of the early days of this company. I'm having visions of the MVP involving 0 lines of code, one cell phone, one inbox, and a whole lot of hustling. "Hiya skeptical restaurant manager, I'm calling to place $1,800 worth of food orders for next Thursday. Also, I want to do it twice a week for the next six months. Do I have your attention? Great, here's what we're going to do..." Repeat a couple of times while becoming the Official Food Logistics guy for the YC mafia, and suddenly you have side of the two-sided market bootstrapped from zero to "You are their favorite person ever", plus you've got a very good understanding of what sucks about ordering food for a large number of people. Then you start coding.]
The YC connection is a great way to get started (incidentally, the YC company I'm currently at (Greplin) has been using them for a few months, and I have no complaints).
Hustle + code = greatness.