Oh, by the way, after doing some research for myself, I've found that it hardly 'cripples' them. A small number of them are in any way crippled. Look at it this way: They are fed steroids, fed enough to plump them up, and get their head chopped off in the prime of their life instead of turning old and crusty. It more or less balances out to what you think is more worthwhile, living or not. Think of it this way, without KFC, all of those chickens would have been worse than dead, because they would have never existed.
Should chickens be not stomped on? Sure, why not? I don't see why KFC Corporation would have a clause that says, '14a. All employees in the care of chickens are allowed (3) chickens per day to stomp, throw against a wall, or otherwise maim.' That's not good for anyone, so I think noone is going to argue, 'Hey, what's wrong with throwing our chickens in a lake?'.
This is important stuff. But I think genocide and wars where many, many humans are dying every day from mistreatment should be the top priority, not chicken stomping.
I would also like to remind you to collect your facts from more than one reliable source. PETA is known for showing videos and other merchandise that is hardly related to the corporation they are attacking, and also for spreading rumors that have been proven false. Ask your friend to cite his sources.
Someone I'm related to, I'm not sure how distant, but it's fairly far, owns a mink farm. If you don't know what mink are, they're like weasels, but people use them for their coat. Anyways, PETA came one night, trespassed, and set most of the mink free. 90 percent were killed as roadkill. To quote that lady I'm related to, "You could go on the road the next morning and make yourself a coat." PETA has a lot of blood on their hands, even if they don't like showing it.
Also, read through these Maddox articles, I found them funny. They're more focused on PETA than animal abuse, though.
http://www.thebestpageintheuniverse.net/c.cgi?u=grill
As madmatt said, I'll support your issue, but never PETA.
http://maddox.xmission.com/sponsor.html