I think it all depends on other things.
My wife and I live in a 45 year old 1200 square foot rancher. We don't spend money on going out to eat, or taking annual vacations, the newest car we have is a 2002. Instead we focus a fair amount of our financial resources on the boat so I would say our % is higher than most, and I would say our boat PURCHASE price was a higher % of our annual household income than most people.
If you're questioning it - take up golf!!
If I had 300k a year in income - I would be sporting this http://www.offshoreonly.com/classifi...o25200-en.html or a Nortech 50V, and I would probably keep the Cafe Racer and let my little brother who lives in the same neighborhood use it - I don't like the idea of not owning at least one boat with the "1" on the side!!!!