Sathi pratha was inhuman, no doubt about it. Raja Ram Mohan Roy reformed it and things changed.
The historical reason for Sathi pratha was to ensure the Muslim invaders do not take away the women of Rajputs. In my understanding the warrior communities practiced it.
The point is valid. There are wrong things in every religion. And all of us must try to reform. Why this does not happen in Islam? I asked elsewhere this question - Why they want to continue barbaric systems like stoning to death, honour killing, killing if one does not wear hizab, .... One of the recent cases of 200 lashes for a rape victim was such a travesty of justice, but the Saudi Law Minister praised the judges for 'applying' their mind and being kind to the victim. The merciful (!) King then pardoned the rape victim of the sentence imposed by the learned, humane judges. Stone age living in 21st Century!!
Killing on any pretext is wrong. This must be stopped and banned at at all costs. Why is there a such a lack of liberal thoughts in Islam?