I think it's perhaps more random than that. Friend of mine had a problem with an older MBP. He took it in to get repaired, it was going to be a system board replacement, but since they didn't have that part handy they just sent him out with a brand new MBP with comparable (but slightly better) specs than his original.
For all the people complaining about Apple, they haven't screwed me over yet either, I've only had good experiences. All hardware, I haven't had a software issue I couldn't find the fix for on my own.
I assume your friend had Apple Care, in which case it would be expected to receive a replacement device if they cannot repair it or cannot repair it in a timely manner.
He did, but it was out of AppleCare too. The kicker was that the problem had begun to manifest while still within the three year window, so there was documented history. It was most of a year out of AppleCare when it failed the last time and they decided to cover it as goodwill.
For all the people complaining about Apple, they haven't screwed me over yet either, I've only had good experiences. All hardware, I haven't had a software issue I couldn't find the fix for on my own.