Well to me it is for the same reasons only better then the Port option.
As now we can serve a site from either web server by simply changing the IP. So we can offer clients a choice of which server to use, LiteSpeed or Apache. They can choose which to use to serve their site, and not have to forfeit links by having to change port numbers.
To me it is a much better option then the port option, so if only one should exist it is the port option I would drop.