If it's anything like Facebook, the side entrances (which always had guards sitting by them anyways) were all converted to alarmed fire exits. So the fire marshal would still be happy, but it was far less convenient for employees.

Instead of locking they could alarm when opened. Slap a big "Emergency exit only, alarm will sound" sticker on it & link it into the pull alarm system. Treat opening the door without an emergency the same as pulling a fire alarm without an emergency.

Amazon employees can just use all the ...water... bottles they keep around their workstation to put out the fires.