When I see articles like this and numbers like that one, I can't stop thinking, why? Why are people doing this? Why are people so ignorant?

I can give you my short answer to why we waste so much.
Because in most cases it is more profitable for those in food business to waste it.
Its that simple, someone is making more money the more food we waste.

Others have worked out a system to minimize food waste and to feed those in need.

In my opinion are these "solutions" part of the problem. Everyone is in need of food and we should not create systems where people who have too much can decide when we should dump the food waste on the "poor", just so we can feel a little bit better when we continue to buy more food.

The people who have too much should eat the food waste first, as they have a choice when consuming. Only when the problem is on your own doorstep will do something about it.