Not to mention the costs go up if you demand prompt service, since there needs to be more slack in capacity.
In certain places like NYC they skirt around this by not having on-staff delivery people, and simply contracting the deliveries out piecemeal, on-demand... The trick to supporting this is, of course, lax labor laws (I wouldn't be surprised if most of the delivery people aren't making minimum wage), and an enormous concentration of restaurants to justify the supply of an independent delivery force. This is unrealistic in a lot of jurisdictions.
I tried working for one of those 'food taxi' companies, who provide delivery from a selection of restaurants that don't have a dedicated staff. There was a $10 charge or $15 for food from two restaurants. The restaurant staff generally didn't care about moving fast for me as a driver as it was relatively rare. And the customers weren't inclined to tip because they assumed that $10 or $15 they paid went to me, which of course it did not.
After these experiences, I just don't think the people that want fast food delivered would generally tip enough, or be OK with paying any delivery fee that would cover costs + profit for the fast food company.
That said, interested to see how this works. It's a novelty because people love In-N-Out, there's a slick web component, and it targets a relatively well-to-do audience in San Francisco.
In high school, the McD I worked at sold food to one of the local school cafeterias, so we had to cook over 200 burgers and fries all at once. By the time we were done, the oldest burgers were about 5 minutes old, same with the fries. After delivery, the food was a good 30 minutes old. Made me shudder, but the stuff was insanely popular at the school. I guess the cafeteria couldn't cook their way out of a paper bag.
This obviously changes as density increases.
They charge pretty ridiculous delivery prices, on a $15 meal I pay $15 delivery, and I assume the time that it takes to place the order, collect the order and deliver the order mean they're not making great amounts of money on that $15. They do deliver well though, when my food arrives it's been <15 minutes from McDonalds to me so it's always delicious.
Something I've been wondering for a while is why don't places like McDonalds, Burger King and In-N-Out do delivery? The only conclusions I can come to are that either they make money by upselling extras in the restaurant and someone ordering from home exercises greater constraint (eg: just ordering 1 burger and fries) OR that delivery isn't as profitable. Does anyone here have any experience in fast-food and know why?