I guess that calls for a re-examination of what Amazon/Google's most frequently ordered items even look like and whether there's much/any cross-over between that and what people walk into a 7-11 to buy.

Though the picture immediately suggests that such a kiosk would have to support asynchronous browsing and order compilation. So that one is not stuck behind a person trying to choose between two candy bars and then 3 bags of snack mix and then... Luckily in 2013, most everyone has a reasonably powerful and competent mobile device in their pocket.