Apple's not the only company who does this kind of stuff but is guilty just the same.
I lived in the UK for six years and wasn't pleased about the markup when buying Apple gear over there (at one point a PowerBook was pretty much the same in UKP as it was in USD, which was like 40% markup to UK consumers).
When the BBC interviewed Steve Jobs at the iTunes UK music store launch, he was asked why songs in the UK were 79p which was a difference of like 50¢ over the US price. Steve blamed the VAT but when told he was still way over the US price he got angry and stopped the interview.
EDIT (UK - US comparison): Currently the $2,299 PB is $2,881 USD with VAT in the UK - but adding 17.5% (UK-VAT) to the US price would add up to $2,701 (so what's that extra $180 for)?
Also the US Apple store will only ship to it's region and Apple has a stipulation in its reseller agreement that only allows them to sell in their appropriate region, too (although you may be able to find an online reseller who will send a US PowerBook to you).
I lived in the UK for six years and wasn't pleased about the markup when buying Apple gear over there (at one point a PowerBook was pretty much the same in UKP as it was in USD, which was like 40% markup to UK consumers).
When the BBC interviewed Steve Jobs at the iTunes UK music store launch, he was asked why songs in the UK were 79p which was a difference of like 50¢ over the US price. Steve blamed the VAT but when told he was still way over the US price he got angry and stopped the interview.

EDIT (UK - US comparison): Currently the $2,299 PB is $2,881 USD with VAT in the UK - but adding 17.5% (UK-VAT) to the US price would add up to $2,701 (so what's that extra $180 for)?
Also the US Apple store will only ship to it's region and Apple has a stipulation in its reseller agreement that only allows them to sell in their appropriate region, too (although you may be able to find an online reseller who will send a US PowerBook to you).