Those have nothing to do with these kinds of exploits. That one is rather a cloning thing done with hardware afaik.
Yes, it's very different and it just exploits a very particular part of the system, but the point is that you can't simply ignore these and say 'nothing will come from it' because nothing happened with the PS4.
The PS4 was exploited, in one way or another, to a point where piracy was achievable, so of course, every exploit like this, has potential to lead to something more significant. No one would have thought that cloning the bios and harddrive on a PS4 would enable you to activate your account on an infinite number of primary PS4s, in the same way no one knows what an exploit via the web app, would lead to.
As a disclaimer though, I don't advocate piracy and neither would I describe to anyone how to do it. The above description is a vague approximation of the PS4 exploit.
Surely you mean $100 on top of the normal PS4 price, right?
Well I believe you can either bring in your own PS4, or buy one at one of the stores. So it's $100 for the exploit but only assuming you own a PS4, otherwise it's whatever the system cost, plus the value of the exploit. I would not be surprised if some of these retailers install hacks as a means of selling units. Sounds more appealing if a pre-owned PS4 comes stacked with games.
Different stores would have different prices. I mean, it's an illegal market, it's not like the prices are regulated. Those are just the prices I've heard people speaking about. I've also heard people talking about $100 for 10 triple A games, and things like that. The people that vend this stuff can charge whatever they link, inventing their own deals as they please.