The last time the Dockers played Hawthorn in a final at Subi Oval, the result was a decisive win for Freo. And although my memory may be getting frail with age, I seem to remember a lot of moaning about the 'difficulties' of travelling all the way to Perth. Again, I may be befuddled, but the last home & away game against Hawthorn at Subi also resulted in a win to Freo and similar moans about travelling to WA being 'hard' for Melbourne teams.
All of which suggests that Hawthorn get away with minimum interstate travel, they don't enjoy the experience and don't cope too well with it either.