Because there are so many ways to mount it and make it look like the way it should, without having to deal with the other problems associated with the plates.
Not picking a fight, but what exactly are the problems? I have plated the last 2, and won't even consider any other option. If I had to run A/C, maybe I would have to do something else, maybe not, never tried it. I love the simplicity, ease of installment, and strength. I've never busted a motor plate, but I've ripped up plenty of stock mounts. I like the look too.