A very good example of what NOT to do! If that bakkie rolled (and it looks like it was on the point of doing so), those guys on the back would at the very least be critically injured ... and if they survived they would most likely be crippled /maimed for life. Who wants to live with that responsibility for the rest of yours.
There should be no persons on the back when negotiating such obstacles. If for some reason you are carrying passengers on the rear, it would be safer to stop and let them alight before attempting the obstacle.
Sorry Pierre, this is not intended as an attack on you, but as a forum that promotes safe and responsible off-roading, we would be seen to condone such practises if we were not to either remove the pic or comment correctively. I believe the second option to be the more constructive.