I think all of us "In the Land of the Hopefully Addicted" fall into this when we see something in a store.
These days, all of my "dress" clothes are used mostly for cruise or special nights out so I go for function. That's why I've gone for suits over tuxedos since I've lost weight.
On other parts of my wardrobe I purchase things that I can wear for things other than cruising. I vowed to never have the Costanza Cruise Collection
(From the Seinfeld show) where certain clothes are kept in the attic and only used for cruising.
One nice thing about a new cruise is that it gives you a good reason to buy some new clothes.