Is it your contention they are irrational? Your contention is that this was great police work, the police would have been prosecuted for murder if they had shot the perp during the course of the robbery, and that the prosecution depended on the testimony of the civilian clerk, as if a police officer had been in the store it would have somehow affected the ability to prosecute the bandit.
Yep, I'd say that those contentions are irrational.
I can tell you from personal work history experience having worked in a support role for a SWAT team in San Diego, CA that this is the way they should have responded... Why? Because it was exactly the way they responded... Am I still irrational? And so now, you are questioning the response of a SWAT with impeccable qualifications...
I'd call that ungrateful...