I watched it again with friend last Sunday.

And I found that the movie has another reference to The Beatles - Carl & Allison sang "Can't Buy Me Love" in the Hollywood Bowl.

And from Wikipedia, learned a few things too:
- Jim and Zooey share the same birthday in real life.
- Actually, at the end of movie, the reason why Carl can get so many donated clothes was because - he went outside of convention centre, and asked the attendees if they could "donate the clothes"

Since they can't say "No", so they end up being naked in the seminar.

I'd take it as a sweet revenge to this "Yes" covenant and it's beautifully sarcastic enough at the some time :)