Are you only interested in solid food or would you want to buy Soylent/Joylent as well? Soylent/Joylent and Meal Squares are so simple that you wouldn't need new restaurants. They could easily be sold at, say, Starbucks.

On a related note, drinking Joylent has improved my feeling of well-being more than anything else I've done. The low price is just an added bonus.