Yes the same is true if your account's main currency is HKD. At the moment the interest rate for borrowing USD at IB is 1.56%
http://www.interactivebrokers.com/en/p.php?f=interest
One could argue it's best to buy USD so one doesn't have to pay this interest. But when the dollar crashes relative to HKD or EUR we will lose a lot more than 1.56%. That's why I'm keeping the account in EUR for now.
I'm no Forex trader. But if there was a reliable robot that could switch between EUR/USD I'd make use of it. Maybe there is such a robot out there, I don't know ... google shows a lot of results for forex robots, but I'm willing to bet 95% of them are scams.