Kirk complains about not being allowed to drive a car, but in I Can't Get Started (2002), his car was blocked in by Christopher's Volvo at Sookie's rehearsal dinner. Clearly, he was driving at some point.
During the baby shower, Sherry's friend, Gayle, is shown standing in front of the window with one of the party poppers. In the next shot she jumps up off the couch on the other side of the room.
When Luke asks Jess what his Walmart discount is, he responds with 15%. In actuality it is 10%.
When Rory and Lorelai are egging Jess's car, they only throw them at the front part of it, including the hood and windshield. However, the next morning there are deviled eggs all over his car, including the side doors and windows, as well as the trunk.
At the baby shower, Lorelai says her main inspiration for raising Rory was For Keeps? (1988), the 1988 Molly Ringwald movie about teen pregnancy. But based on Rory's age in the show, she was born around 1984 or '85, meaning the movie would not have been out yet.
At the baby shower, Sherry's friend said she was surprised when Sherry got pregnant because she isn't a baby person. Sherry agreed and said Christopher is the baby person, but when Rory and Lorelai first met Sherry, Rory spent the day with her and came back telling Lorelai that Sherry wanted 2 kids and was considering doing it on her own before meeting Christopher.
At the baby shower, no one is supposed to say the word "baby". Yet, during the game where they are shoving cotton balls into the bag, Sherry continually says the word baby and no one takes her pin or corrects her.