Such behaviour from crowds are not in good taste. But, the Australians complaint sounds like "they hit me back". Besides being good at Cricket, they are also experts at psychological fight thro' their media and their unnecessary aggression on the field.
If the Captain himself is unable to or is uninterested in controlling his own team from sledging, how does he expect a control of thousand of spectators? Ponting should understand that such crowd behaviour happens often to the Australians. There should be a good reason for this and being Cricket Champions is not one of the reasons.