Someone arrives with dozens of books to sign

Sounds like maybe it was a bookstore owner or book reseller (who would then offer them on eBay or Amazon Marketplace). Authors often sign dozens of books for later sell when they do a book signing.

There are quite a few people who are full or part-time book resellers. They used to show up early whenever the local library had a book sale (often there were many donated "Like New" former best-sellers and such at the sale for one or two dollars). The book resellers snap them up and then sell them on eBay or Amazon.

I was at a book sale one time when one of these resellers was there (it's pretty easy to identify them). One of the older women running the sale thought he was an avid reader and complimented him and started asking him question about his wide-range of interests. I guess the guy didn't want to tell her the truth so he just offered some vague answers in reply.

I suspect the "collector" at the festival was one of those types. Collect and sell.

Many bookshops limit the number of copies an author can sign for any one individual. Some even allow only books purchased at the signing to be signed. This sort of thing is probably what has led to these kinds of policies.

Frankly, I'm surprised that bookshop let someone get 140 books signed. If I were the manager of that shop, I would've limited the guy to 10 or maybe 15. That's just common sense, plus courteous to both the author and all the other readers.

What I appreciate is when someone with more than a few books waits to the end of the queue.

Yeah, it struck me as odd at a book festival where people literally had milk crates of books--mostly used--for the author to sign.

But if they are used books, the author has already made his/her money and there would be no benefit beyond "I'll scratch your back, you scratch mine." But if I were the author, it would be hard to know if the person with one copy of each of my books was a bookseller or a fan. If someone had a bushel basket of books, though, I don't know what I would do. Schedule to sign them at another time so as not to hold up the line? But I'm sure this would consume the entire day of a big name author. Hopefully some day I'll be a big name and can come back and tell you what it's like

I wonder if all those books had remainder marks.

Never heard of that many being signed but then I have not been to a signing since before the days of ebay, which may be a significant point here...

When I went to a signing by Michael Moorcock I had my entire collection with me (only about 10 books I think at the time) and he signed all of them but asked if it was ok if he only put a personal dedication on the first couple and specifically picked out my first edition of Elric of Melnibone for this treatment. I still have that book on my shelf almost 20 years after...