If you lose, wouldn't you like to know beyond a doubt that you fairly lost? Know if you were unlucky or fleeced. That's what provably fair allows you to do.
Provably fair does not necessarily mean provably fair.

When it comes to anonymous cyrpto currency in an unregulated gambling market, I'd expect numerous operators to pull every trick in the book to screw over people.
For example:
http://www.reddit.com/r/Bitcoin/comments/1frm4x/provably_fair_by_bitzino_not_provable_with/If something isn't provably fair or if people do manage to figure out problems with the PVF system then once thats out, the site loses on a lot of players . People should always do their research before blindly trying out a new site. I doubt reputed site operators would pull any trick in the book just to cheat people , they would actually be losing a large chunk of their revenue by being fair.
"I doubt reputed site operators would pull any trick in the book to cheap people"
This statement has been proven UNTRUE time and time again over the past decade...from small time operators like BLR technologies to regulated UK gaming companies..."irreglarites" have been FOUND ALWAYS resulting in the house getting an advantage above average.
Do not believe that just because a site publishes a "provably fair" system then that is all there is to it, if they want to cheat they will cheat you. That reddit thread just details a FEW ways a provably fair system can give you VERIFIED fair results and still have cheated you, I'm sure they dozens of more ways.
Point being, I trust software such as Netent or Playtech(both of which are not provably fair) more then any bitcoin casino flashing a provably fair badge...
