They can't climb smooth vertical surfaces so your safe there, and there are ways to avoid touching them if you want to get creative. Grow them in the one bin method, when you want to harvest them use a spoon, spatula, flatish ladle etc.... or put a slice of bread, let as many crawl on it as you want to feed out then feet the chickens the whole slice of bread worms and all. I know it doesn't seem like it now, but you really do get used to it.