You should grow your own. Super cheap to do that, and there are lots of threads on here on how to do it. I have a large-ish shoe box of wheat germ and started it with a little tub of 500 worms from petsmart. It was a challenge to not give all 500 to the beady little eyed chickens that were...
good to know . I've had leftover indian and thai food that I've never bothered trying to give to them because I thought it would be too spicy and disrupt their digestion. I'll have to ease my flock into that then....
I've given my chickens (uncooked): whole-uncracked oats, cracked oats, instant oatmeal...and they've been happy with them.
As for leftovers....I use a pet bowl for foods that might attract varmints if left uneaten (stuff with meats, oils, fats). That way, the the chickens don't eat it, I can...
cleaned out the freezer of some abandoned White Castle burger (ick). Food processed into crumbs while still frozen. The chix seem to like the 'rat meat!'