They are usable in the market they were sold in and the environment is better protected if their disposal is done in a professional manner which includes accounting for disposition of any hazardous materials.

By sending to a "country of need" we immediately run the risk that end up in the countryside or disposed of improperly and that unless you just happen to land in a country with sufficient infrastructure to even support the devices they just end up as curiosities.

It is very easy to be altruistic when no analysis is involved in determining the true cost of such actions. As in, many ideas sound great on paper but are so unfeasible to actually worse than doing nothing.