The typical response to this is that euthanasia opponents are living in a dreamworld, and lying to themselves. It is obvious at its face that some lives are not worth living, and to think otherwise is foolish.
On the other hand, the euthanasia opponent can reasonably ask how can we both support euthanasia and have suicide prevention hotlines? The existence of both seems to indicate that our societal response to an eagerness to die, rather than being about individual choice, is more about encouraging cultural norms about who is to be valued.
... struck directly in the head, from behind, caught completely unawares by something moving at several times the speed of sound, with enough size and kinetic energy to very quickly dissociate my body's molecules with negligible loss to the impactor's velocity. A rocket would do nicely.
I know that there's no sensible way to justify the expense for one person's almost-certainly (based on current understanding of physics and biology) painless death.
But a boy can dream. ;)
...I think this is the most macabre thing I've said all year.
So, $7 for the round plus the going rate of a professional hitman.
I suddenly have a very macabre desire to crunch the numbers on that vs. a traditional open-casket funeral these days. ;)