Depending on how hard your wrists sit on the laptop I could totally see that as and issue. The case is pretty sturdy. My old powerbook had the same thing. I know the guy before me was not rough with it, but a lot of hand pressure and the way the laptop is stored could be viable reasons.
For people who seem to think that Apple hardware is just junk, lets just say that OS X is only half the reason I have ran Macs for so long. The other side of things is the hardware.
If people think that a Thinkpad is better then a MacBook Pro as far as build and hardware. I have had 5 Thinkpads in my group at work need replacements within a few weeks. I have seen no problems with my MBP (Knock on wood) and only the slightest cosmetic defect appeared on my powerbook, but I guess the grass is always greener🙄