Comment I think you can upgrade them (Score 1) 477
I've heard that a co-worker of mine upgraded his MBP's SSD and RAM.
This website, http://www.everymac.com/systems/apple/macbook-air/macbook-air-faq/macbook-air-mid-2012-how-to-replace-upgrade-ssd-storage.html, seems to imply that the only thing you need is a funky screwdriver.
Back in the 90s, when computers cost $5,000-$10,000 in today's dollars, it made sense to keep upgrading them. Now the top-of-the-line computers are cheap enough that it's easier to just buy one that you can afford to replace every 4 years or so.