Unique promo codes have to be generated somehow. Integrating that generation into probably outsourced survey mechanism is likely not exactly trivial and may (if

Unique promo codes have to be generated somehow. Integrating that generation into probably outsourced survey mechanism is likely not exactly trivial and may (if not done right) open ways for anyone to generate any amount of promo codes they want. This is one kind of problems you get when you start separating different functionality into separate applications that don't known about other parts.