There are plenty of white people i know who don't try to act like anything and are some of the best dancers i know.
I pretty much lived in the carnival for 12 years (ladbroke grove). It doesn't matter what creed, colour or religion your from AT ALL. Just have fun, eat and drink.
And remember, there are MANY different floats with lots of different type of music ranging from calypso to house.
So what im trying to say it who cares about what colour you are, just have a good time and dance if you want.