Suppose for the sake of argument I managed to secure some sort of annuity that pays just enough to subsist on, starting now.
Knowing that I'm guaranteed enough income to stay minimally solvent does not mean I have no reason to care about losing additional income streams that enable me to have things like vacations and dinners at nice restaurants and digital watches.
Similarly, the relative security of the ~1/3 of Boeing's revenue that comes from government contracts is probably small consolation to its shareholders. They do that business more-or-less at cost; essentially 100% of their profits come from other sources.
Also, the "plus" part covers both overhead and profit. So, depending on what your overhead situation looks like, profit can still be minimal or non-positive.
