Trivia: The names of the SavMart employees announced over the in-store P.A. are all the names of famous photographers.
Trivia: Robin Williams has the same last name in this as his character does in Jumanji; Parrish.
Trivia: Jack Nicholson was originally cast as Sy and Robin Williams the manager at the mall, but Nicholson turned the role down and Williams requested Sy's role.
Trivia: In the scene where the boss tells off Sy for being rude to the technican, you can see the photos of the employees on the wall. As we see later, Sy's photo is the one in the second row at the very right. In this first scene his photo is tilted while all other photos are perfectly straight. In another scene later in the same room, a security man holds the photo in his hands and asks for a copy. Both scenes were shot together and the photo was improperly put back to the wall, which explains why it is tilted in the preceding scene although it was not supposed to be taken off the wall by then.
Chosen answer: This is mentioned on the DVD commentary - it's deilberately open ended so one can interpret it as either it's Sy imagining what he wants to happen OR it's what really happened.
Neil Jones
As Neil Jones said, the ending is open for interpretation. However, I think there is reason to believe that Sy imagined the photo. It shows him and the family outside of their house, all looking happy together. Would they want to take such a photo with Sy after the incident at the hotel? And before the incident, they were probably not close enough with Sy that he would be in a photo taken at their home. Him and no other guests/visitors.