I like some proprietary apps, but there are those that I have never used, like Health and Tips, and likely never will. (I know, I know. Never say never.) A few of which I have accidentally opened, but not actually used.
There are those apps like Passbook which have only used once or twice – I wish I could remove it when I’m not using it, along with any other app that falls into this group.
Then there are those that I would just rather use a competing app because I like the interface better.
I have better things to fill up my iPhone’s hard drive with, like toddler selfies of my toddler’s toes or nose.