Not even remotely the same. Alluminum isn't all equal. iPhone 5's are actually notorious for having a bezel that's made of really soft alluminum that gets nicked easily
Understatement of the year. Remember the aluminum PowerBooks that replaced the titanium ones? Before the current MacBook Pros with the "chiclet" keyboard?
I worked for Apple when those were new. I swear you could dent the damn things by breathing on them. We had a lot of angry customers.
Same goes with this phone... yeah, we should be more careful (leave my crash out of this; that'd have destroyed it even in a case) with them, but the fact remains that some devices are more durable than others. If you want a Nexus 4, you have to take appropriate precautions to protect it because it's not the most durable device out there. It's all a design trade-off: they could make it more durable, but it'd be heavier and less attractive to look at. It's not as if the design is somehow defective--it doesn't break when you use it, only when you drop it.
My backup phone is a Samsung B2100. Not only can I throw it and drop it, I can drop it in the swimming pool. I have dropped it in the river and gone back to fish it out. I simply toss it in my bag with all manner of heavy and pointy things. I'm not careful with it AT ALL because it's designed to be abused. The N4 isn't, so don't abuse it.