It's a style choice, and I think both the choice to utilize it and the reception to it are heavily dependent on the participant's cultural background and upbringing. A lot of people see this kind of message, applied to someone who Really Should Know Better, as a form of tough love and half-tongue-in-cheek way to place extra emphasis on an important message.
Some people can form that understanding as the basis of their relationship and continue on happily, able to both give and receive this kind of criticism. To others, it is completely foreign and incomprehensible and they don't see the tongue-in-cheek at all and just interpret it as blatant, outright hostility, which is generally not the actual subtext.
Some people can form that understanding as the basis of their relationship and continue on happily, able to both give and receive this kind of criticism. To others, it is completely foreign and incomprehensible and they don't see the tongue-in-cheek at all and just interpret it as blatant, outright hostility, which is generally not the actual subtext.