Why can I expose private members when I return a reference from a public member function?

Question

In the code snippet, I am able to access the private member variable outside the class scope. Though this should never be done, why is it allowed in this case? Is it a bad pract

Answer 1

Returning private members as reference is perfectly valid and the programmer who writes a class is responsible to carefully choose if this should be allowed. This link gives an example when this can be done.