This is an example by (of all people) the civil servants in the Department of Defence her in UK.
I used the "Contact Us" option on their website to put in an enquiry about the reasons behind a particular policy, and within a few hours I received an e-mail acknowledging my enquiry but informing me that it could not be answered by e-mail because that would expose the Department to "unacceptable volumes of unsolicited e-mail" (civil-servant-speak for spam?).
So they think that an e-mail containing requested information could give rise to spam, but the e-mail that told me that could not have that effect?
Whichever way you look at it that is peculiar.