Transcription:
With the Oxford comma:
we invited the strippers, jfk, and stalin.
[A picture showing a cartoon image of 4 people. JFK, Stalin, and 2 strippers.]
Without the Oxford comma:
we invited the strippers, jfk and stalin.
[A picture showing a cartoon image of 2 people. JFK and Stalin, both dressed in the same stripper outfits as the strippers in the above image.]
“Supposed to” is…debated. Some style guides like the Oxford comma, some don’t.
Personally, I’m a strong proponent of it. It never creates confusion, it often removes confusion, and it always does a better job of visually representing natural speech patterns.
It absolutely can create ambiguity, just in different circumstances. The truth is, people should just pick a format they like, and be vigilant about possible ambiguity and reword the phrase if it is unclear.