Those things are approved by the Islamic equivalent of tax consultants...
Its like a Sharia law avoidance scheme... for some of the accounts its a case of we'll not pay you interest, except we actually will but we won't call it interest but an 'expected profit rate'... and get a wise bearded guy who also believes in the same nonsense you do to approve the scheme.
Thing that gets me is - if Allah exists then these muslims are surely a bit retarded to think that implementing some avoidance scheme to get around his rules on ursury is going to go down well. Do they not consider that he might look at it in the way that HMRC views Jimmy Carr - essentially as someone blatantly taking the **** out of the rules. I mean its like taking your girlfriend up the rear to avoid the no sex before marriage rule on the interpretation that that rule just covers the pink hole....
Still like most religious people - they tend to pick and choose the rules that suit them best...