Revealing mistake: When Sam and Jerry watch the billboard, a blue car passes by and the driver slows down and stares at the filming.
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Lights, camera, relationship - S6-E5
Revealing mistake: Right when the episode starts, a group of bystanders gather to stare at the filming.
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A woman's right to shoes (a.k.a. no shoes, no service) - S6-E9
Revealing mistake: When Charlotte and Carrie walk down the street there's a group of bystanders behind watching the filming. One of them is even taking pictures.
Answer: I'm a long-time fan of the show, having re-watched it many times, and I definitely remember slightly different dialogue at the end of that episode than what's on my DVD. I'm afraid I have no idea why this change might have been made or any other info, but you're not insane.
Purple_Girl