Comment by icegreentea2

It's true that in principle, you need a stronger rocket (the whole rocket, not just the motor) and a bunch of extra infrastructure to be able to reuse.

However, without being able to recover a rocket, it's actually quite difficult to figure out just how much corners you can cut, while remaining reliable. Since blowing up revenue payload is an awful way to optimize this, I think this means that disposal rockets will be inefficient in a different way - there will be excess safety margin in the wrong areas.

Reliable re-use also changes the operating model of the company. Since each rocket in stock represents many customers over time, you don't need to be nearly as stressed about exactly matching your manufacturing pipeline to predicted demand. This likely also enables generally faster turn around time (as in from cheque signed to launch).

Finally, as it turns out, it's not unreasonable to expect a rocket to be reused like 20+ times. I think you're point would be reasonable if it turned out that reusing a rocket more than ~3-5 times was difficult. But like... it's REALLY hard to do disposal anything better than something that can be reused 20+ times.