My belief is that being able to not see stuff like that gives a much stronger sense of ownership of the device. It also removes you from an endless treadmill of software updates to something you don't use (some of which may even force you to restart your machine). Following someone's guide to perform hacks to remove something that the OS vendor clearly expects to always be there is both a hassle and likely to cause unforseen consequences in the future, so I don't really agree that the desire is actually solved by the existence of these guides.
Not from Apple it isn't.
* Adding 128 GB to a MPB = $200
* 512GB SSD on NewEgg = $100.