BLOODY BANKS!

As you probably know (and for those that don't) I'm purchasing a near new second hand car. I got a personal loan, and because of my job as a carer for my father (who has a serious heart condition) I was able to release my superannuation funds early. With much signing of papers, doctors letters, mechanics assessments etc, I managed to get my cheque last week. I deposited it into my cheque account at my bank which I have been a customer for 21 years. I was informed that my cheque would not clear for 6 working days. WHAT THE FUCK??? The company I have my superannuation with isn't likely to run out of money. So why so long? I asked my bank, they told me that if the cheque was from Western Australia, it would take 2 days to clear. Because it was a cheque from the Eastern States (New South Wales, I think) it would take 6 working days. If it was an overseas cheque, try 30 working days. I don't understand it. With technology these days, why should it take so long? I thought banks had a system where they could interact with other banks. In this day and age, I find it ridiculous.