Child Brides in Afghanistan

A high proportion of marriages in Afghanistan involve girls below the legal age, according to reports from the Ministry
of Women's Affairs and NGOs. As many as 57 percent involve young women under 16 years of age, some of them as young as nine. More often, than not these young girls are married to middle-aged men who have had wives in the past and may even have children from previous marriages.

I did some independent research and found that according to Afghanistan's new constitution, the minimum age of marriage
for females is 16 and for males 18. However, in rural and even some urban areas the tradition of marrying off daughters while young in order to receive money remains common among the poor.

Are these young girls then seen as a commodity that can be sold off? How desperately poor would her parents be that they need to marry her off in order to be able to provide for themselves?