Sorry but I think you’re wrong on this, the way I’ve had it explained to me it works is for example my site would be
217.112.82.16/~highroll
and another site might be
217.112.82.16/~casinorus
They would have exactly the same underlying ip address just that http://www.high-rollercasinos.com would resolve to 217.112.82.16/~highroll and the other website would resolve to 217.112.82.16/~casinorus. This is why it’s so dangerous.
The way to test this is to simply type in 217.112.82.16, which is still my underlying webserver ip address, with my dedicated ip address pointing at it, and see whether or not you can reach my site.
It could well be that different hosting solutions are different from mine but I don’t really see why they would be.