Many accounts might be created by a single person for this purpose, which I think it is still not really worth it and I will explain. Anyone could create an unverified account like you said, but what is the essence of trading on different accounts when you will still eventually forget some of those accounts, and a user may eventually forget the password or details to the wallet where he has so many of those coins just because of some sort of discount.
No matter the amount of discount, you cannot trade a fund in more than one account at a goal,. And having to split those funds will be very stressful, and also to me, this is cheating which may eventually invited strict regulation on unverified account. Binance is already a big platform, so it would do them no harm if they start introducing KYC to the unverified accounts now.