What i know of Nikah in Shia is to have a contract in order for the guy to **** the woman and have sexual pleasure for a limited time such as one month of sexual relationship and of course the woman's parents are paid for selling their daughter or to be leased to one man then it can be leased next to another so i believe it is a little bit better than prostitution,i don't mean to be offensive here but that is how i see it,it is kind of business which sex is involved.
So you avoided replying to the proofs given above that Mut'a is an islamic marriage that was practiced during the life of the prophet and abu bakr before it was cancelled by Umar, and instead you started to repeat the old accusations of your imams...
Be sure that what you described is not applicable to Mut'a, as muta'a have conditions such as the Uddah (waiting period after the marriage) etc.
You need to read about other forms of marrige which are available in wahhabi islam (and other Islams) such as marrying-with-the-intention-of-divorce