Visible crew/equipment: During Johnny's surgery, the top of the set is visible over the door area when the camera angle tilts up, just before Morton comments that there's blood and wonders where it's coming from.
Visible crew/equipment: After they load Johnny into the ambulance, just as it's about to pull away the reflection of the location's array lighting is visible on the back of the ambulance.
Visible crew/equipment: When Roy and Brice are taking vitals of the possible heart attack, depending on the angle of the shot, the outlines of the mic transmitters can be seen on the backs of Roy's and Brice's shirts.
Answer: It is standard practice to wet down driveways so that they stand out in a long shot.
stiiggy