What does the classical Shia scholar al-Tusi think of Mutah?

He narrated in his “Tahzeeb al-Ahkam” (7/253):

(1089) 14 – واما ما رواه أحمد بن محمد عن ابى الحسن عن بعض اصحابنا يرفعه إلى ابي عبدالله عليه السلام قال: لا تتمتع بالمؤمنة فتذلها.
فهذا حديث مقطوع الاسناد شاذ، ويحتمل ان يكون المراد به إذا كانت المرأة من اهل بيت الشرف فانه لايجوز التمتع بهالما يلحق اهلها من العار ويلحقها هي من الذل ويكون ذلك مكروها دون ان يكون محظورا.

As for what is narrated from Ahmad bin Muhammad from Abu al-Hassan from some of our companions which is Marfu’u to Abu Abdullah -alaihi salam- that he said: “Do not humiliate the believing woman by having Mutah with her.” and this Hadith has a Maqtu’u Isnad and has Shuzouz in the Matn.
It is possible that what is meant in this narration is that if a believing woman was from a noble household then it is not allowed to have Mutah with her as it will dishonour her parents and disgrace her and this would be Makruh (Disliked) without it being forbidden.”

Other shia scholar al-Hurr al-Amili in his “Wasailu shia” (21/26) narrated:

 [ 26432 ] 4 ـ وعنه ، عن ( الحسن بن علي ) ، عن بعض أصحابنا يرفعه إلى أبي عبدالله ( عليه السلام ) قال : لا تتمتع بالمؤمنة فتذلها . 

 قال الشيخ : هذا شاذ ، ويحتمل أن يكون المراد به إذا كانت المرأة من أهل بيت الشرف يلحق أهلها العار ويلحقها الذل ويكون ذلك مكروها . 

 أقول : وتقدم ما يدل على الجواز ، ويأتي ما يدل عليه . 

4 – And from him from al-Hasan b. `Ali [Abu ‘l-Hasan – in at-Tahdheeb, Abu ‘l-Hasan `Ali – in al-Istibsar] from one of our companions going up to Abu `Abdillah عليه السلام.  He said: Do not do mut`a with the mu’mina as you would humiliate her.

The Shaykh said: This is shaadh (odd), and it is possible that his intent by it is when the woman is from a noble family which scandal would be attached to and humiliation attached to her, and that would be disliked.

I say: And there has preceded what indicates upon permission and there is coming what indicates upon it.

I ask the Shia why would Allah allow this “Mutah” if it will bring disgrace and dishonour to the girl and the parents?