People who have spent time in these areas (not as tourists) often notice the hugely damaging effects of many charities. If Western societies had relied on charity in pre-industrial times, they might never have been forced to develop strong institutions and welfare systems. Instead, they might have evolved into begging cultures.
These systems are incredibly difficult to develop because doing so goes against our selfish nature. In Tanzania, across Africa, and in many other parts of the world, people often care only about their own circle—in other words, their own family and kin.
I do believe wealth should be shared. It shouldn't be a choice; it should be an obligation. But not like this.
The ultimate goal of charities should not be to enrich individuals, but to help them build cooperative societies capable of supporting the most vulnerable.
I believe your donation only makes the problem worse. Helping people is much harder than simply giving money to someone in a way that makes you feel good about yourself—without even getting into the many Western NGO workers who profit from posts like this.