Andre,
The issue I see with two contacts (emergency and standard) is that
everyone will email the emergency contact.
I fully agree that the response required for 1 spam email vs 10000
emails is vastly different, however, if someone wants a response they
will email the account they think they'd get the fastest / best response
from. It's just human nature.
Whilst at first non-emergency complaints will be ignored, it will get to
a "boy who cried wolf" situation where the amount of non-emergency
emails vastly outweighs the emergency emails. To the point where the
organisation will just treat the emergency mailbox the same as the
current abuse mailbox.
You would need some disincentive to email the emergency mailbox. Like on
a train where if you pull the emergency handle without there being an
emergency you get a fine. I'm not advocating a fine here, just something
similar to try and regulate emails coming into the emergency mailbox.