One other thing that DOES comeninto play here: Its not like we have the option of upgrading iPads with extra memory ourselves - kind of like you CAN skip the factory stereo upgrade at the car dealer and proly get one thats better for half the price aftermarket. In that sense, Apple DOES lock you into buying this stuff from them and ONLY from them. Its called a captive audience and therefore they can overprice the memory by about 17,000%
And, no SD card takes that option away too. Its "smart" on their part but IMO thats kind of lame. In most cases with products the consumer has more options and has some control over the upgradeability of the product. Apple locks you OUT!
Why not look at it the other way around? The 32 GB is the sweet spot, balancing the on-device storage with the access to the environment, whereas the 16 GB is sold as a minimal on-device storage with environment access, offered at a margin below what the company is willing to make on the device, yet attracting users? I'm quite confident the 16GB is a viable device when you go for homesharing and active cloud usage.
I don't believe is the attractiveness of a memory card extension. How so? From a promotional offer, I got a Samsung tablet with as low as 8 GB of memory. Well, the thing looks nice and works fine - albeit way less intuitively than the iPad - ... yet time and time again, it tells me it doesn't have enough memory to install or run things like Skype ... even if I have a 32 GB additional memory card inserted ... Well, it might also be me just being stupid, of course
That's the whole difference: after two years of using the iPad (Gen2), I still find it great ... after using the the Samsung tablet for a fortnight, I lost interest in it, and use it only when I don't have another option.
Still, one caveat: this is an opinion inspired by a promotional model; I'm quite sure Samsung makes decent stuff also, and then gets in a similar price range.
It's a matter of what you like and want to integrate with.
But never think adding a 16 GB memory card into a 16 GB device makes it even to a 32 GB device ... not by far.
A nice day to all of you.