This is arguably another problem with such messages - they should probably
go to the envelope return address (from the SMTP MAIL FROM command or the
return-path header field) rather than to the author's address (from the
From header field).
That will get them sent to the mailing list manager, who certainly will not
care to learn which of the thousands of mailing list members are on vacation
at any given time.
Of course, the mailing list manager also does not care to learn which
mailing list members have exhausted their disk quotas either, but hundreds
of mailservers are very happy to tell him to please send the message again
later.
RFC 1211 should be required reading for anyone developing a mail server.
Perhaps then the developers would at least take mailing lists into account;
it's pretty clear that most of these systems are designed on the assumption
that mail is one-to-one.
With regard to the reply from Microsoft, note that the issue of sending
vacation messages to the Internet is completely orthogonal to the issue of
sending vacation messages in response to a message from a mailing list.