Because the people that live in those developing countries are fellow human beings, and generally have no economic/political power relative to Facebook and other MNCs.
This excuse has very often had the result of denying basic jobs and services to people in developing countries.
Like the GP said, "alternate ways" are imaginary until someone else does it. The best way to provide an alternate solution is to provide an alternate solution. The worst way to provide an alternate solution is to complain about it with that typical rich Westerner indignation that some people face harder choices than themselves, with the end result sometimes being that no solutions at all are provided.
