Dear Shopping Mall,
signs like this are dumb to me. They hurt your sales. You do not permit me to show my friends what I like about you.
But you do not allow me to guide friends who may like to see what it looks like in your mall before they commit to the trip.
Maybe you wish to prevent photos by the competition so they cannot easily copy your mall or spy on prices inside.
I bet you did not know that competing sales staff have been using cell phones or buttonhole cameras for years and people shop the internet for prices.
So by your own decision you do not want additional visitors who may turn into customers. Fine with me. I respect that. I will not even tell them where I photographed this sign.
Or is it because friction rewards intent and creates scarcity?
P.S. Upon second look, if only photographing is prohibited, using a different camera to make a video for YouTube is OK with you?
Update: With all the surveillance cameras going, you might even find out what people take the most photos of and make that more of an attraction. Read why shopping was boring in 2002. And it still is.