This argument does not work. More it risky than the first flight of F1, which had a client payload? Than the first flight of F9, which carried a boiler plate Dragon?
Surely that's the call of the engineers who actually build the thing? As we have said to hoax believers on this board often enough, the people actually doing the work are under no obligation to share your view of how things should be done.
Even if they could not find a client, is a car the best they could come up with themselves?
No, a mass simulator was the best they could come up with, and since it doesn't matter what a mass simulator is made of, why not something with a little visual spectacle to create some great PR and iconic images?
You keep dancing around the question of whether you'd be objecting so much if they'd just put a simple mass simulator on it and made it a pure engineering test flight. Your whole objection seems to be based solely on the fact they made it a bit fun.
If it was so risky, why only one test flight?
Because it was an untested configuration of otherwise proven hardware? Come on, the Saturn V only had two test flights and one of those suffered such problems that engines shut down and bits fell off it. And although they had CSMs to test the re-entry systems, they didn't put any kind of LM on board either of them. Was an inert test article the best they could come up with to pad out the payload? Is that somehow objectionable? (Yes, I know there wasn't an actual LM ready for Apollo 4, 6 or 8, but they had this thing with huge payload capacity that they could have shoved some other functional thing on, surely, if we follow this argument.) Risk management is a matter for the organisations running the launches, not the general public.
And what was so risky about it?
Again, not your call.
Even the side by side configuration had been flown before,albeit in liquid plus solid configuration.
Which is not at all the same as three large liquid cores strapped together.
"Too risky" smacks of post hoc reasoning.
And your entire argument smacks of disdain for a bit of publicity that still does not detract from the success of a test flight. I ask again, if they had just flown a plain old boring mass simulator would you be objecting so strongly?