The European wasp is an introduced species and therefore does not have natural predators in Australia to keep their numbers low. In Europe, the cold winters ensure that only the Queen wasp can live, but the warmer climate of Australia means the entire nest can survive.
European wasps are a pest because they are far more aggressive than native wasps. The European wasp is an increasing problem in Australia.
This insect likes to live around humans because of the ready supply of food and drink (sweet).