not really sure wamu allows it
1. i would like to take advantage of:
rewards structure
intro rate
bt offer
2. i would like to put this card's limit in line w/my others
3. i am expecting to make a major purchase and would like to use this card, but don't want it maxed out.
really your limited only by your imagination, the above are just things that pop in to mind.
oh, i usually call the number on the back of the card, before calling the number on the sticker. a good amount of the time the activation number is totally automated.