Playwrights Must be Driven Mad

I just curated an author's play reading series in a library. I invited writers, told them to bring "5-15 minutes of something that is a good sample of your talent"'-- that will be appreciated by the kind of people who generally go to literary events at a branch library. We had an hour and 40 minutes, 6 pieces should take an hour leaving 40 minutes for tea and cookies and question-and-answer where the Library Ladies will get to know the authors and perhaps-- who knows?-- become advocates for the local talent to be produced by local theatres.
One writer-- whom I had never met, and included on someone's recommendation-- brought 6 actors and 40 minutes worth of scenes from her full length play. I'd scheduled myself last and had to cut the piece I was performing to about 3 minutes, and there was still no Q & A time.
What was this writer thinking? Why would she be so rude and burn her bridges with a "producer" -- however humble-- just so that an audience of fewer than 50 Library Ladies heard 40 rather than 15 minutes of her play????

Our lives of quiet desperation must drive us mad!