Comment 7 for bug 298617

To do this would be a simple change in debian/control to drop it down to Recommends in ubuntu-standard. Perhaps there is a reason for it being the way it is, hence the explanation above, i.e. please open an idea on Ubuntu Brainstorm. If enough people get behind this idea it can be implemented. It is preferred to do it this way since it is a change to the default options of an installed system.
I have marked this Wishlist, Confirmed for now, but again, please see Brainstorm or alternatively one of the Ubuntu IRC channels, perhaps someone higher up in the chain of command can give you a better explanation or push this through.
Thank you and good luck :)