I'm gonna cut to the point here.
Apple makes products that look good initially, but are super susceptible to damage.
Examples: MacBook Pros & Airs, iPads, iPhones (4, 4S, 5), and the iPod Touch.
They are easily scratchable, dented, cracked, etc.
Think about it: have you EVER seen an Apple product that uses aluminum high quality enough, to where it doesn't easily scratch? Even if they're not as sensitive as defective iPhone 5s, they're STILL easily scratched.
Pick up a Nexus 7 and an iPad, and look at the back. Then ask yourself which one you'd feel more comfortable setting on a table, maybe even sliding it along the table, etc. I'm guessing you'll say the Nexus 7. Why? Because the back isn't made with anodized aluminum!
I'd love it if Apple started making their devices with plastic, rubber, leather, etc. Something more scratch/dent resistant than what they use now.
We have to face it, Apple clearly hasn't put damage-resistance at the top of their priorities list. I find it interesting how people mention the iPhone feeling more high quality. Yeah, it may look good now, but it could look a lot worse later on. And if you decide to put a case on it to protect it, you cover the device's beauty (unless it's a bumper). Kinda lame, isn't it?
Doing normal day-to-day things can scratch your Apple devices. It's annoying to me. I don't want to worry about how I set my MacBook Air down, because I may scratch the sides. I don't want to need a case on my phone in order to protect it from small scratches.