Oh, that's cool. I've never worked in a building big enough to need more than a couple people in a mailroom to handle that. Also, I guess I've never had my mail screened for sarin.

"Mailing facility" doesn't have to mean "warehouse", it can also be "we want to use more fancy words so we'll call the (large) mail room a mailing facility".

At the larger bay area companies, it's usually an entire office building dedicated to nothing but processing mail. Similar to college campuses.

I think "warehouse" is an appropriate term in these cases. :)