The fridge on Princess is actually cold (unlike RCL - when you put a glass of ice in it, it melts in no time at all ... with Princess they put the ice bucket in it and it stays as solid cubes). Princess usually has a bottle of water in the cabin and you can have the steward take it away. Yes, you can put your own soda, pop, etc. in the fridge and your own wine ... you are only charged the corkage charge on wine if you bring it to the dining room - not if you drink it in your cabin. As to the soda card, it's only good for fountain drinks (no cans or bottles) that you get at the bar.
As to the question about the robe ... you can always have the robe but you often have to ask for it ... no charge - and it's a very nice robe. One less thing to pack.
Filling out the Preferences neither means that you'll receive them nor be charged for them - they're running a survey ... no big deal. Guess if you're in a mini-suite you might get some of these things but have never had a mini-suite.
You also can have a bowl of fruit in your cabin - they'll have a form for you to fill out stating your preferences as to what (banana, apple, etc.) and it can be replinished by the steward ... this, too is free.
You'll love Princess - I do.