Yeah Coles Online here is advertising them at $4.98/kg (or 90¢ each), Woolworths Homeshop is advertising them at $1.03 each, weird pricing.
The reason why they're so expensive is that bananas are the ONLY fruit that is not allowed to be imported into Australia, thus the price changes due to the season, bananas are still the biggest selling item in Coles supermarkets.