I wonder if in the case of most of the girls, they do not have responsible parents? This might be an alternative to foster care or homelessness. I wonder if many of them are referred by social workers? Or if they do have loving parents, possibly there is a situation that needs very close daily monitoring that can not be achieved in the home - and the child is given the option of Mercy Ministries or a hospitalization or more traditional RTC. This may be a kind of "forced" decision, but nevertheless, it would at least be another option for some girls; and I suspect in many cases, a far better option.
Its the upper end of the scale I find a bit odd. I speculate these women may be trying to break a drug habit; get away from an abusive situation; or possibly they are trying to cope with mental illness.
Frankly, I greatly admire what Mercy Ministries seems to be doing for these girls. I am much impressed with the zero cost. I don't know how they do it - but I feel this surely indicates a real heart for helping - and not some warehouse rip 'em off and beat 'em up scheme.