I understand why the OP and others are eager to dispel my thoughts as idle and without experience. Reality is just not as fun as the imagination. A little perspective:
I have backpacked thousands upon thousands of miles on foot.
I have lived out of my backpack (no car) for significant periods of time, both with a fair amount of money and with next to no money.
I have traveled extensively.
I have spent significant time in Africa. This includes both the bush and more urban areas. I've walked barefoot through a mall with a large knife on my side, as I had disavowed shoes and wanted to believe that I was an authentic Afrikaaner. I scaled the border fence between Botswana and South Africa, then was confronted by an armed guide with an AK-47. I've been up close with the elephants, with the crocodiles, and with the cobras. I've been on a real safari (not the sissy photography type, but the type that Teddy Roosevelt went on, which ends up with an expensive taxidermy bill). I'm familiar with some of the local customs, certainly familiar enough to know that I could never completely familiarize myself with them.
Understand that racism is alive and well in Africa. This goes both ways. There are hotels, restaurants, where no black people are permitted. Equally so many of the natives strongly dislike caucasians. This is understandable. Parts of Africa are in absolute poverty. Poverty like you couldn't imagine. We blame Africans for poaching rhinos to sell their horns on the black market for a few bucks. Yes, this is absolutely wrong. However, when faced with the fact that your sons, your daughters, your wife, and you are going to starve to death, can you blame them? In a similar light, do you really think your life, a young Westerner clearly out of his element, will mean anything to these people other than a few bucks for your possessions and currency?
The US, for the most part, is extremely tame. We do not have the wealth disparity that Africa has. Almost no one is in such poverty that their family is going to die from lack of protein. Botswana has the highest HIV rate in the world. In many parts of Africa the HIV rate is 25% or more, of everyone. These sick people really have nothing to live for, and access to no health care. They will not hesitate to relieve you of your possessions, and possibly your life. You cannot simply hitchhike, backpack, or camp. It is not possible.
Yes, Africa is very poor in general. There are exceptions. However, to be safe and in some comfort, you will have to pay for "white people" accomodations. These are geared toward the wealthy traveler. There are few to no poor white people in Africa, and certainly no poor white travelers. It costs money to conduct yourself, especially if travel is a primary concern.
I hope I am effectively painting the picture that the true Africa is far removed from whatever pay-to-volunteer project you were based on, surrounded by other similarly doe-eyed Westerners. I love Africa, absolutely love it. I have done a tremendous amount of research on it, as well as have spent a considerable amount of time there. I can name every animal by sight, throughout the expanse of the entire continent, from the tiny forest duikers to the magnificent sable, to the diminutive rock hyraxes. I know the subtle differences in the different calls of the lion, how to recognize if an elephant means business or is simply inquisitive. I know how to handle a gun in the bush and how to handle myself among the people. You do not.
If anyone ever told you that I give a damn, they damned well told you wrong!
The other day I was eating Starbursts and watching TV, and then a Starburst commercial came on. I was like, damn, that's profound.