Average price paid for electricity in many regions is 20 cents/kwh. Just using your numbers that translates into $300/month in costs for under $400 in ETH.
At the national average it would be $200/month by rough math.
But the regions where people are hosting miners are between 2-4c per kWh. Those are the competition, and those are the people buying (and selling) these.
2 cents is what you're competing against -- very large mining farms located near cheap, under-utilized hydro plants. Many in China, due to the existence of many such plants. [0] Those are the mining operations that can remain (marginally) profitable when the small home miners are forced out because gross revenue is less than power costs.