Keep in mind, you are paid in Bitcoin, not in cash.
Your pay is dependent on the price of Bitcoin, or, whatever people are wiling to pay for it.
I still run mine despite a gross strain but still make good coin, I have 8 running and make a half decent amount of coin.
If you run them free them it's no big deal, if the price of Bitcoin was $10,000 then you wouldn't be asking this question
I run them because I think they look bad-a$$ and they heat my basement, which means I save on heat =D
NOTE: Keep in mind, you are paid in Bitcoin when you mine Bitcoin, you get cash when you trade your coin.