Why order at the drive-through itself?
Fast food outlets all have drive-throughs, and they are popular though sometimes it's hard to figure out why, since you get a slow simulation of being stuck in traffic. "Oooh, are we going to move! Yes, he's released his brakelights!" You may also have heard that McDonalds is outsourcing the order-taking part at some restaurants to teleworkers in the midwest, where wages are lower. (Not India, yet.) They reason that there is no reason the order-taker, who just punches the order into a computer, need be at the actual location, and in fact, when things are at their most busy, it makes sense to put everybody onto filling orders, not taking them.
You go to a board with a menu and a bad intercom to place your order. Why do this? Cell phone penetration is very high now, so why not phone it in? Either a direct number for that restaurant, or an 800 number where you can say which branch you are at or going to. You can't see the menu but you probably know it, and the order taker has the time to help you through it. They might be at the restaurant if they have spare capacity, or might be in a call center entering it on the computer. They can tell you pretty accurately when your order will be up.
Yeah, I just re-invented phone-in takeout, but this time based on the drive-through concept. Worst case you call it in while already at the restaurant, which is where you order today. But if you think about it, you're phoning it in on the way there. And they might tell you, "You know, it will be 15 minutes here, and just 3 minutes at the branch down the road" to load balance.
Now when you get to the restaurant, you probably should just park in the lot and go inside for your order. But they could also have a parking area with an LED display with the order numbers (or even sufficiently unique suffixes of phone numbers) displayed to say who can now enter the drive-through lane for instant pickup.
And of course, if you want to pay on credit card, and they know you, you can even pick up the food without the timewasting cash-handover.
This makes more sense at make-to-order places than at McDonalds of course. And it can apply to more than fast-food, though usually only fast food places have computerized order management. Perhaps people might order better food if it were more convenient?