Mostly, because all that would do is cause is random inflation and inequity. When donating money, you are reallocating resources. That can lead to improved eco

Mostly, because all that would do is cause is random inflation and inequity. When donating money, you are reallocating resources. That can lead to improved economic growth, if for example you are allowing people to go to school, start businesses, or otherwise helping build such bridges. More times than not, donations cause long-term harm. Look at oil in Nigeria to see how a massive simple influx of cash was not good for the population. If you really want to help in Nigeria, you can help mentor a university student there. Your time will count for a lot more than your money. Or if you are willing to spend money too, hire a university student from there as an intern (likely remotely). That helps align a lot of incentives.