Religious courts such as the Beth Din make people feel uncomfortable.
In principle, why shouldn't two parties subject themselves to their jurisdiction? It appears to be just another sectarian and divisive absurdity of religion. As long as their decisions stay within national law, I see few problems other than those inherent in religion.
For instance, it is true that women are often dominated and manipulated in Islamic communities in the UK and do not feel in a position to challenge their menfolk. They tend to accept the iniquities of Islamic justice for the 'sake of Islam' and a peaceful life. That is their choice. One can help those who challenge unjust religious practices but it is much harder to assist victims who support their own delinquency. It is difficult even to uphold the law that protects teenage children who 'willingly' accept child marriages.
It all seems part-n-parcel of the daft Abrahamic religions.