I see the knee-jerk "RACISM" response has been invoked in most of you. None of you were there, and no one knows exactly what happened except the people directly involved. How can you immediately condemn the airline for their actions without having first-hand knowledge of what was seen, said or done?
There are many many other things airline staff would find "suspicious" other than the color of their skin - maybe they were whispering to each other, maybe they had no baggage, maybe they were sweating a lot, etc. We just don't know.
Don't immediately assume it was their race or religion that got them kicked off the plane.