Correct me if I am wrong, at this point it's not 'not-profitable' because of the electricity bill but because of the cost of the device. Ye?
A large mining operation may be manufacturing their own miners and thus have a "purchase" cost for the miner that is a lot lower than the commercial product. They would also pay low energy cost by buying bulk (they are an energy company's best customer because the load is constant in contrast to other data centers) so they should get a good deal. Ergo cost for a commercial miner operation is quite a bit lower in short and long term compared to hobby mining.
A commercial miner has to report to authorities about the operation and profits and they need to lower the risk of price volatility. They can either sell the coins as they mine them, which would put pressure on the price, or they can lend the btc out if they believe this is a short term down and they want to own them long term. Either way they get a firm fiat value for their coins today that the tax authorities understand and can deal with and they can pay their utility bills.
So the OP has a point in my opinion. At what price is the equation sustainable?