Predictive Easter Egg To The Addams Family In Back To The Future (1985)?

In this video I share a brief possible future nod to The Addams Family series of films present in 1985 time travel comedy Back To The Future. Actor Christopher Lloyd played Doc Brown of this, inventor of the Delorean time machine. Lloyd later played Uncle Fester in The Addams Family in 1991 & Addams Family Values in 1993.

Shortly after the opening Marty McFly travels back in time from Hill Valley 1985 to 1955. He goes into Lou's Cafe at around 36 minutes 41 seconds into the movie. There, we are introduced to younger version of Marty's future father George & later a younger version of Biff and his gang (including a character played by Billy Zane). Marty later looks up the address of Doc Brown and here I thought there may be one of two possible homophone based references (based on the root ADD - ADDITION & ADDAMS) to The Addams Family:
- In the scene at around 37 minutes 5 seconds Marty is trying to call Doc Brown's number (with no success). His wristwatch is clearly shown (and is a digital calculator type made by Casio capable of multiplication, division, subtraction AND ADDITION).
- Later Marty has an interesting exchange with Cafe owner, Lou. After asking where the location of Doc Brown's address is, Lou becomes agitated and asks Marty: "Are you going to order something kid?" To which Marty responds: "Gimme A Tab." The request is misconstrued by Lou who thinks he wants to start a running bill, but I think Marty was asking for a diet TAB soda (not introduced until 1963). Lou replies: "I can't give you a tab unless you order something." To which Marty requests a Pepsi Free (not introduced until 1982). Lou responds: "If you want a Pepsi you have to pay for it".
This dialogue also I think hints at the concept of mathematics, addition or possibly valuation - perhaps an (unintentional??) future hint to The Addams Family.