There are some things that charities do not want as they make their money by selling the stuff that people bring in. Medical items are one of the things they do not want as they don't know what they have been in contact with. They do not send the items they are given, out to the aid areas as it is too expensive, it's all converted into money and that is turned into the things they actually need like food, medicine, transport, fuel.......... The only thing that goes out in the form it comes in is medicine and first aid type stuff. The charities normally do not handle this stuff either, this is handled my the volunteer doctors and missionaries, a completely different group of people, they may also take on the used medical equipment.
Very true. The other big one is not knowing how they have been stored, critical with many medications. Even stable things like paracetamol should not be exposed to more than 25c - something they can exceed in moments left in the sun in a car.