Absolutely - they do cost money. But the point is - you still need them for digital. If you read the Holt piece you can see he's actually taking on extra staff. I thought his comment about how production was turning into software development was very interesting. A lot of books now aren't just Kindle files they're apps too -- and app development is incredibly expensive. 

Then there's the work involved in maintaining very extensive web sites and dealing with the occasionally very thorny issue of metadata. And any way you look at it print will be around for years to come so you couldn't get rid of those people. Unless you abandoned print altogether of course, which some small publishers have done in the US. 

But I can't see any major company going that way, can you?