Would you rather he'd sent a block of precisely-weighed concrete into space, like other dummy payloads on other booster tests? I disagree that it's worse to send a publicity stunt instead of something more...respectful?...boring and completely useless.

I do agree that there are better things than publicity stunts to do with dummy payloads. You don't need to launch a multi-million-dollar satellite, but it would be low risk to launch a low-cost payload with corner reflectors for laser identification and distance measurement, chirping radio transmitters, or sensors, clocks, or radios for telemetry.

You can construct a Cubesat for on the order of $10k, but it used to cost 10x that to launch and now costs about that much for a SpaceX rideshare to SSO. Surely you could construct something with at least a little utility to use as a dummy payload.