Let's be real. One of the few restrictions that might keep the poor(not minorities, the poor in general) from having a proper drivers license is the costs of vehicle registration, inspections(in some states) and the cost of the license itself. All tolled, can get to be very expensive all at once, thus a person that cannot afford it all might end up just getting an ID.

Though, for this reason, state issue IDs generally work for identification as well.