Reno, Reno, Reno. First up, go to Burger Lord instead - the damn burgers from McMoogles are absolute crap. (Comment from the Zack in my head: the burgers from the trooper's canteen are better than McMoogles burgers... and given the general standard of food from the trooper's canteen, that's saying one hell of a lot). Better yet, head down to that little corner shop down near the border with sector seven Topside run by the couple from Wutai, and get the burgers there, because they come on a toasted bun, they're cut in half for you so you don't lose half the contents on the first bite, and when they say they do a burger with the lot, they *mean* the lot.
Secondly, if you *must* go to McMoogles, it's quicker and easier to go in the front door and talk to the warbling teenager behind the counter in person, rather than hope the drive-through won't distort things. Even if Meteor is dropping from the sky, it'll still be quicker and simpler to do it in person. If all else fails, send Rude in with the order, if only for the laugh value.