amazing rules in Qatar

One thing i noted in Qatar is , most of Qatari owned companies are holding back driving license of workers , what profit Qataris can get by doing this . Isn't possible to get another copy of driving license from Qatar Traffic department ?

also many Local owned companies are applying for new visa then canceling the same for workers who requested for cancellation of his work visa , Do they also get virgins in heaven as a reward for doing this ?or what-else benefit they will get from this