At work, I've been given the task of contacting our suppliers, explaining who we are and what we are doing, in order to update our information on them.
Of the ones that reply, most send back the form and supporting documents without issue. Some ask a few questions before completing the form, others want more time to studi it. However, today I got a reply asking who I am (I had already told them), why I wanted this information (I had already told them), and went on to say that my email asking for help was bizarre and offensive.
They graciously allowed me to reply, but only if I have a legitimate reason. They then added that they will send my request to their legal department anyway...
Oh, such fun...