We have had completely opposite experiences then. I have almost never never had a corporate or government entity require a functional scan in a production environment. Some have started off asking for one but in the end I have never had one actually do one. They always end up balking at the need to supply credentials and are uneasy with the risk to the stability of production system inherent in a functional scan. Instead they settle for the non-functional scan from the expensive subscription tools such as Qualys which they use.

The majority of time these reports are being produced to fulfill an auditing or FISMA requirement and not considered worth the risk to systems a functional scan could present.