"a drive on a carefully programmed route" - given careful enough programming, this appears to allow for an indefinite amount of smoke and mirrors specific to this demo.
3/4 of McDonalds and other restaurants I go through already have signage, road markings, etc. for the drive through. Even some of the McDonalds I've been through have signs in the windows saying "Window 1" and "Window 2" (why this is necessary for humans of an age and intellect capable of driving a car, but apparently the ability to count windows does not have an impact on motor vehicular ability).
It really wouldn't be much difficulty for the companies to standardize these signs as most already use their own anyway.
I just hate the "drive up and we'll bring it to you" bit.
Awesome, if you ask me.
This was discussed in a past patent mentioned on HN.