Why would you not pay an illegal immigrant if he was busting his behind for you? Isn't that slavery?

I wouldn't hire him/her in the first place. But since illegals are scamming the system by working under the table while paying no taxes, I guess some get what they deserve. Isn't it interesting that unemployed citizens aren't permitted to congregate and look for day labor? And when they try anyway the illegals usually run them off, often VIOLENTLY. Who protects them? NO ONE!!!