I've always made chili from scrap food I have in my fridge and leftovers. Ground beef, steak, chicken, black beans, a variety of chiles, a shitload of random spices and hot sauces like daves insanity sauce just to add heat, onions, and I like to add a little bit of bbq sauce and honey to add a little bit of sweetness.
I've never followed any "rules of chili" when making it. I just throw lots of random shit in there including corn with my only primary guideline being that it be composed mostly of beef and heat.
My chilis are always good. But until now I've been completely unaware that I was violating chili law, and frankly I don't really give a damn.