As an applicant, I understand that whatever you put at the low end is what you are going to want to offer me assuming I just minimally pass your bar. To get the higher end requires negotiation. However, if you are willing to pay my x+5, why bother with the games at all? Just make your best offer and let's get things off on the right foot. Why do we need to feel like we each "got the better out of each other?" It also levels the playing field for people that just aren't good at negotiating.
I'm an engineer, not a sales negotiator. What does my ability to argue for a higher salary have to do with my ability to build product. Probably nothing. And if you think this is some coded way of measuring ability to convince people in a discussion, maybe you should explicitly be asking that during your interview process instead.