 Why did Morgan turn on the lights at Infield & Morgan when Reggie entered?
Infield stepped into the main stream of human traffic and tried to adjust to the second change in the air. A young man with black glasses and a radar headset (a photophobe) was unable to keep from being pushed against Infield. The magnetic suction dart dropped away from Infield like a thing that had been alive and now was killed. Men hide in the comforts of insanity, but when faced with death, they are often forced back to reality. Infield looked up self-consciously and noticed that they had crossed two streets from his building and were standing in front of what appeared to be a small, dingy cafe. A man could cut his wrists with the edge of a sheet of paper if he tried long enough, so of course the Bible would be imaginary.
 Because he was sensitive to sound, Morgan's Cure was wearing ear protection. So he had to turn on the lights in order to read Reggie's lips.
 The room was too dark, and he wanted to see who had entered his business so suddenly in the middle of a bad storm.  He wanted to surprise Reggie with his presence so that he could dismantle Reggie's Cure easier.  Because he was sensitive to sound, Morgan's Cure was wearing ear protection. So he had to turn on the lights in order to read Reggie's lips.  In his shock at the news of Infield's death, Morgan turned on the light so that he could see Reggie and make sure he was telling him the truth.