New Literary Discussion Lows

Today, I overheard the following conversation between two of my coworkers (by the way, I work in a publishing house):

Coworker A (while recommending a book she just read to Coworker B): It's like [popular book title that was recently made into a feature film].
Coworker B: Oh, I didn't read that.
Coworker A: Neither did I, I saw the preview, but you know, it's about [blatantly off-base explanation].

SIGH.
It already annoys me to no end when people attempt to have discussions about books, based on the movie they watched. But I think explaining a book based on the trailer for a movie you haven't even seen, is a new low.
This has been my pet peeve of the day rant.