It's a curious thing.
In fact, that curiosity is my real motivation. I don't really worry about my digestion this much, except that it presents an interesting puzzle. Since I have to buy food anyway, it becomes a hobby with little added expense.
I think the human body is adaptable enough to make do with just about anything. For an individual, unless they have unusual problems, there's little evolutionary damage that can be done. My child will survive whether I burp or not. But messing around like this gives us some data on the question of the optimum human diet. Thanks to the internet, we are on the verge of being able to aggregate that data into meaningful information.