Kullervo, expect that most people in an average classroom won't know PA's reputation, including the teacher. There are tons of creative writing teachers who think PA is a legit venue.
I recently got a mail from an aspiring writer wanting advice on how to get an agent. He said he'd published two books and had several more ready to shop. He was "ready to take his writing career to the next level."
In the time it takes to type *THIS* far in this post, I'd Googled his name and found the two 120-page titles selling for 22.95 each were with PA.
Well, *I* knew they weren't professionally published, but clearly he did not. It was a tough writing my reply. I pulled no punches. It wouldn't have done him any favors, and besides, I have warnings against PA all over my website, which he'd have had to gone to to get my mail addy.
People see a picture of the book with the writer's name on it. Who bothers to notice the name of the publisher? Most will be impressed.
They will think this person is truly pro-published, and it's impossible to impart sense into them when they're waving that overpriced book around.
They will certainly make excuses for the formatting errors, bad spelling, and grammar goofs, along the lines of "every book has typos" or "but the story's so good you don't notice those things."
Walk on, write your book, and let the lemming either figure it out when the royalty check arrives or let him drown. The last thing one should do is talk sense into them when they're celebrating.
Maybe later one could ask, "Why did you choose to sign on with a print mill instead of with a real publisher?"
They will either be ignorant about the difference, say that they didn't have enough money to pay a publisher (tell them about Yog's Law), or trot out "other publishers rejected me, but PA accepted it."
Asking if they could point out other PA titles in the store
might cause them to ask why there aren't any, but some people will never figure it out.
They're in the honeymoon stage. By then it's too late to point out they're staying at the Bates Motel.