[quote="ubergeneral"]There is nothing wrong with taking scans and posting it on a site and making money, as long as they get permission from the scanners of course./quote]
The problem is, Mangafox doesn't get permission, and while they claim to respect the wishes of the scanlators, the hard truth is that the site does not. All they care about is making money.
As for why have two sites doing the exact same thing - more money, of course! Both sites make money, so that's more money the owner pulls in every month. Also, some people might use Mangahere instead of Mangafox because they've had about how Mangafox doesn't care about scanlators. They think they're avoiding the asshole site when they're really not, because the same person owns both sites.
What more do you want? What constitutes a "compelling argument" for you? Mangafox doesn't respect the wishes of scanlators -
this is made extremely clear. Notice how the credits page says, "Do not rehost this chapter. Please don't support websites that do"?
Mangafox is a for-profit organization that only cares about money; there are other read-online sites that aren't just about earning as much dough as possible, that actually listen to scanlators' requests.
To add to how greedy Mangafox is, I remember some time ago, around when OneManga died, Mangafox removed a lot of series due to copyright infringement. Included were Bleach, Naruto, One Piece, and Yu-Gi-Oh (there were many others, but those four are the only ones I remember being taken off, and they alone illustrate my point satisfactorily). With a few weeks, Bleach, Naruto, and One Piece were returned, without any explanation. Of course, no one needed an explanation. Those three series (and the other popular ones that were brought back) were important money-makers. They drew in a lot of people, and the more people that visit the site, the more money the owner makes from ads. With the most popular series gone, the number of people that visited Mangafox drastically decreased. So, to get their profits back up, Mangafox brought back the series, disregarding any possible legal troubles.
They did this solely to keep people coming to Mangafox. This is obvious because they didn't bring back every series that was removed; Yu-Gi-Oh remained removed, and it is still removed to this day. The only series that were brought back were the most popular ones, the ones that generate the most income for the site.