Frustrating guns not being fired
Debatable about how effective they'd be, but there were at least three occasions where police could have fired but didn't/couldn't.
The cop guarding the Blaisedales fired and had a jam, but then it looks like he took out another gun or tried to clear, click again! Then the Swat guys coming through the roof, didn't occur to any of them to use their SMGs as they were too busy running away. And down in the tunnels when the cop with the shotgun is leading the people away, when the beast grabs the woman and rears up in front of him, and he just looks and watches it walk away. Hollywood, I guess.