No $hit! You need to re-read the article. But you CAN blow away a criminal with a gun in your face. The cops put the clerk in danger. They should have supplemented a SWAT officer in civie clothing behind the counter.
What would your reaction be if the criminal SHOT the oblivious clerk?
They waited until he left the store so they could arrest for armed robbery... Until he had left he hadn't committed the crime yet...
Re-read the article before you comment, you are stating the obvious and missing the point entirely.