The entire movie is in Jay's head.
- After the arrest mentioned Clerks II, Jay is going through detox and hallucinating the whole thing. This is why nobody in Clerks II mentions his imaginary girlfriend.
- But without the movie money, how did he and Silent Bob fund Dante and Randal buying the Quickstop?
- Plus the shirt (or hoodie, whichever) near the end - Justice TLF.
- Perhaps, in broad strokes, it really happened, but Jay's drug habit... added in a few details.