For Google/Apple it makes sense, but this is the case with all the handset manufacturers. Like, what does HTC, LG etc have to gain by limiting storage size?
I recently got a 128 GB SD card for my phone and it's great to finally have as much storage for music as I used to have on my iPod Classic (I use Google Play Music All Access, which allows saving as much as you want to local storage).
It has always been standard for Nexus phones to not have SD card expansion [1]. Whether it is justifiable is up for debate. I've always assumed the main reason is so they can sell people overpriced storage upgrades and push people into buying a new device.
1. The Nexus line is supposed to be something like Google's Android reference device, and implements the minimum common set of features -- up-to-date computing hardware and screen, reasonable-resolution cameras, standard set of sensors (GPS, acceleration, etc.). An SD card slot doesn't really add any technical possibilities.
2. Google probably wants to push the idea that any storage beyond local apps should be to the cloud.
(which is comically unviable in Canada, where you're paying $25-50 per 1 GB of mobile data)
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I recently got a Nexus 5 after a long search for a replacement for my stalwart iPhone 3GS. The lack of SD card was the primary sticking point, and caused me days of choice-agony. In the end, price and "cleanliness" (stock android, lack of shitware, doesn't fight software customization very hard) won out.
