Why do we need void functions?

Is there any fathomable reason why we need void functions?

For the same reason that int main() is a standard, why not simply return 0 from a function that doesn't require a return value? I see three immediate advantages to using an int type:
1. We can return a code to indicate function status; typically, if there's a problem, we can return a non-zero error code.
2. We can output the return value of the function when debugging
3. It's the standard for the main() routine; that is, int main() {}. Why not follow suit?

Is there any reason why we'd prefer void over int?

Example: A function that sorts an array of cheeses, and returns it by reference.

#include <iostream>
#include <string.h>

int sortArrayInt(string & _cheese[]) { // pun intended ;D
    int errCode = 0;
    try {
        // ..sort cheese[] array
    } catch(e) {
        errCode = 1;
    }
    return errCode;
}

void sortArrayVoid(string & _cheese[]) {
    // .. sort cheese[] array
    // no return code to work with, doesn't follow int main() standard, and nothing to output.
}

int main() {
    string cheese[5] = {"colby","swiss","cheddar","gouda","brie"};
    std::cout << "Sort Status: " << sortCheeseArrayInt(cheese) << std::endl;
    sortArrayVoid(cheese);
    // ..print cheese array
}

OUTPUT:
Sort Status: 0
brie, cheddar, colby, gouda, swiss