If they took advantage of this situation it certainly would have been bad but I do not think they are doing anything wrong for the customer. Their only downside has been offering to list coins in exchange for money, which means even a scam coin could potentially pay binance to get listed and seem legit and than sell all they have and run, which is bad business but it does not mean binance is doing this out of scamming people, they are doing it to make more money, considering their fee's are low they need to find a way.
On top of that they have a high withdrawal fee which can be dropped to half and even more, however they are not doing it to make more money via withdrawal fee's, how much do you really believe they could rack up on that profit, they are just doing it to keep you from withdrawing smaller amounts and keep on trading for another while. I really believe if customers make a lot of money it would mean a lot more business for them so they really hope we all make a lot of profits so we keep on trading and making them money.