Fake Bidding / Trolling

[Melthyz]

I've been meaning to address this issue for the past weeks. I've noticed an uptick in this "annoyance" of late. I'll provide an example of what i'm referring to.

Example
Selling deed 4m
Buyer: I'll offer 3.5m
Seller: Okay, let's deal
Buyer logs off and vanishes...

Can someone tell me what is the point of this? There is nothing to be gain but to be put on an ignore list.