I don’t think there ever should be a drive-thru Subway, whether standalone or at a petrol station. One of Subway’s main selling points is the ability to customize your sandwiches. Attempting to do so over the speaker just…does no justice to the Subway experience. Even if you speak nonstop and choose your bread, meat, cheese, veges and sauces well under a minute, the kitchen inside will be chaotic. How many sandwich artists can you fit in a Subway aisle? I’d say about four before all hell breaks loose. So why does drive-thru work for McD and not Subway? Because they follow different concepts. You can’t customize your Big Mac. I mean, like customize customize.
However, I do think that having a non-drive-thru Subway at a petrol station (following the One-Stop Center concept) is a better bet than at a shopping mall. Instead of worrying about high rent/ competing with other international franchises at shopping malls, why not open at a location where your customers are more likely to grace your store on a necessity basis rather than a oh-where-should-we-eat-now-Kopitiam-yea-Kenny Rogers-yea-Subway err? (Hint: cash-strapped fresh graduates and busy yet health-conscious office workers). Once you have identified your most likely regular customer base, then you can choose your location.