There are many events that are not catered to specific genders or racial backgrounds. This one just happens to be not one of those.
I guess I can see how an event like this might seem odd to a non-black male.. But America is an odd country where cultural trends are completely deformed (its not just america but let's focus on her for now). This event would just be the first step to show an alternative norm to a girl who has all her life been exposed to completely negative examples of what she can become. This is her Quake.
When the day comes and somebody creates an event called Black Girls Code, and other people: men, women, white and black, completely honestly ask that person "why", that's the day when we can truly call ourselves an equal opportunity and just society. Unfortunately I think this is still quite a ways away.