Subscription prices are... silly

So I finally got home today and the first thing I did was go and make an account and character. However, the prices were... Odd.

I'm not saying that it is overpriced or anything, rather about the maths behind it.
1 month = $1.99AUS
3 months = $6.49AUS
But by doing basic math...
1.99 x 3 = $5.97AUS!!
This means it is actually cheaper to buy 1 month at a time then to buy a bigger package. It may not seem very significant, but in this case I may only have 6 dollars, and I can't buy a 3 month package, but can buy 3 x 1 month overtime.
Is there a reason behind this?

Weird. US prices are:

1 months: $1.99
3 months: $5.99

I suspect Apple's currency conversion is messed up, because the devs specify a pricing tier for an IAP item, and for whatever reason, Apple is turning these tiers into odd currency numbers for Australia.

Definitely strange - Raven is correct though, we don't have discreet control over the regional pricing so something is just odd with the currency conversion. :/