That would make a degree of sense, although unlike people such as yourself and I, who will upgrade to new models regularly. There will be people who keep theirs for much longer.
Then there's the factor of, when I upgrade and someone else inherits my old model, it's life continues. During which time Apple will likely increase the maximum initial download size for apps above the current 200 limit, just as the did on iPhone. That along with a proliferation of new apps could potentially have someone using more storage than the 32GB model has. Not that the second owner is a concern for most, but being the nice, generous chap that I am mine usually get donated to family and friends so there's a part of me that likes to know they'll get a good life span out of it.
I still maintain its always better to have more space that you may not need, than less than you do need.
But, even saying that, the 32 is still a good buy and if the time comes when you have filled it up with apps and goodness knows what down the road, it's nothing that s bit of app management won't fix. Just delete all of the old stuff you don't use. Less convenient, but just as effective.
