While not quite 100% responsive to the structured question, this story immediately came to mind from two and a half months ago, noon time weekday and presumably a combat reload would have been wise....

Oklahoma Man Uses AR-15 to Kill Three Teen Home Intruders

I would also point out the well-covered Trolley Square mall shooting, where the good guy with a gun was extremely limited in the action he could take because he had eight in the gun (IIRC) and no reload. After he took a few shots at the active shooter, he was at a major disadvantage due to low ammo, regardless of his considerable heroics. To the posed question, you do not reload when you lack a reload.

Those real life cases resonate with me because (1) I have been to Trolley Square and the Omaha Van Maur personally and (2) know at least one unarmed person who hid in the back of a store two years ago during a similar mall shooting incident (for hours... in a mostly non-CCW state... waiting for LE to clear a four-story mall). Add in the outlier Nairobi mall as the most worst case along with other mall attacks like St. Cloud MN, Portland OR, et al. The series of mall incidents absolutely reinforces my thought process on what is well within the realm of possibility in any public space, including ones I have personally found myself in.