Cleveland did the same thing when Lebron left them in 2010. How short everyone's memory is.
But, hey, facts are irrelevant when it's more fashionable to bash Miami fans. Look, I was just as ready to point and laugh at them for leaving games early, but this is silly, people. Cleveland fans did the same [dang]ed thing, and other fanbases have done just as bad or worse. Sports fans can be nuts in every city.