All good points. I think this is why the main customer they are courting for this use case is the US military, which doesn't care about many of those things in peace time, and would care even less in war time.
I used to love this idea, but when you actually think it through it's just not necessary / borderline plain dumb. Unless I am missing something, I really hope that US tax dollars are not thrown into this boondoggle.
1. This will come up on any ballistic missile radar as a threat. "Oh don't worry nuclear armed enemy, it's just cargo."
2. Unless it's a one-way trip, this would require huge infrastructure investment for "stage zero" and for logistics required for the oxygen and methane tank farms at both ends.
3. The trajectory is much more predictable than the flight path of say a C-17. This would greatly simplify interception.
4. The landing options are hugely limited compared to say a C-17. There is no go-around option. LZ got hot during transit? Too bad, we are landing!
5. I cannot identify the type of cargo that would be better served by the least stealthy delivery method possible, and most fragile landing infrastructure, only to save a dozen or so hours of transit time. Prepositioning the cargo closer to potential trouble zones and using traditional aircraft seems to be a much better idea in all cases that I can imagine.
But, to attack my point, the utility is very limited - essentially for special ops insertion an hour or so before all the conventional forces show up. A very expensive paratrooper insertion with the possibility of a one way trip.
Even then the Orbital Drop Shock Troopers banging the door down are probably too vulnerable to SAM during the last phase of flight. I guess the hope would be that operators would ignore or be confused by a massive radar blip traveling at high speed before the suicidal burn?
The more realistic case for Starship is shipping lots and lots of military tonnage to orbit. Rods from God are achievable if Starship reuse pans out, and those are truly perfect hour zero weapons before the stealth planes show up.