Why make a PSU that only fits certain cases?

Hardware Hub Cases / Chassis
1

Its beyond me but antec seem to think different, basically upon buying this PSU your agreeing to only use Antec cases, be it may antec make some awesome cases but the fact its so cheap, and to then start only making them available to your own cases. Maybe antec had other ideas maybe the psu was designed to keep good airflow and was tested in only certain antec cases, oh and the psu im talking about is the.
Antec CP 850W Modular Power Supply

But anyway teh point is if this continues then theres going to be a whole lot of confusion? but the good thing is the cases can fit other psu's but STILL! why do this i want every one opinion, i mean every ones, becuase i cant seem to bring myself to see WHY its was done and i dont want antec getting selfish now do we ?

2

i didnt know about this, my amptac pyramid 1000w fits good in my antec 900

3

seems like a good idea, less hassle, you know it will be perfect for the case.

and its like 85% efficiency . so w/e.

4

Antec FTW.
*hugs 900 with Antec quattro 850w inside.

Well it's stupid, yes.. But Almost everyone uses Antec these days anyways : P