It's an arab thing. They just happen to be muslims, you'll never hear of Jews, Christian, Druze or whatever other non muslim denomination of arab there is involved in this kind of thing.
It's also a supply and demand thing, this is kind of the "mail order eastern european bride" thing prevalent in the west, only for lonely old horny arab losers instead of lonely old horny western men, all wrapped up in a 3rd world islamic package with full jugaad halal temp marriages etc.
Pakistan, Indonesia, Phillipines, Malasia.. you can bet it's happening everywhere where old arabs can have their way kind of exploiting the poor.
i am not sure why pakistani and indian muslims look to the Saudis for religious leadership
you have to wonder what is going in their heads