mediamatrix (X) Oct 21, 2009:

Possible interpretation If the account statement concerns services in which the waste disposal company leaves an empty container at the customer's premises for a period of time and collects it when it is full, then 'return service' often refers to the delivery of a fresh empty container when they come to take the full one away. By indicating the requirement for a 'return container', the service provider can hopefully make fewer journeys with his trucks, thus making his service cheaper (or his profits bigger...).
I've no idea how you would refer to that in Spanish...