I don't believe this is really the case. They do have some rules, perhaps sometimes confusing them.

Interestingly, Mindpearl operate the AA call centre in Brisbane and most staff are multi-lingual (They handle calls to AA from Australia, NZ, Japan, China, Singapore, Malaysia and Indonesia). In my dealings with them it seems patently obvious that, for most, English is not their first language - having said that, their understanding of 'Strine is generally pretty good (and one or two orders of magnitude better than the previous CAAll Centre in IndiAA).

More on this topic here:(Note the neo insider posts from Connected1)