That doesn't make any sense.
If you are walking around in the middle of the night it is the fact that a group of guys out hanging around in the middle of the night are probably up to no good that is the relevant information. That would be the case whether the group consisted of white or black people.
If you are walking past a group of black people in the store do you weigh the odds like this as you pass? Of course not. You only do that if you have put yourself in a dicey situation. How do you know that group of black guys isn't the church choir talking on the sidewalk after a late night choir practice? It's the situation you should be in doubt of, not the race of people you encounter.
Just because they are black doesn't mean they are dangerous. The fact that you think that they are and cannot understand why someone else would take issue with that categorization is troubling.