Consumers that are already using (electric) space heaters are already paying $X/mo in electricity. If they are getting value out of a bitcoin-mining space heat

Consumers that are already using (electric) space heaters are already paying $X/mo in electricity. If they are getting value out of a bitcoin-mining space heater, it is justified to run at any time you want heat, because by getting a BTC rebate of any amount would make it cheaper to run than a space heater. If enough miners are mining for the purpose of heat, it will push non-heat miners out of the market, because the heat-miners are rationally willing to mine at any price (any 'rebate' on expected electricity->heat costs is useful), whereas the non-heat miners can only rationally mine when btc reward exceeds electricity cost. (We are a LOOONG way from the majority of miners using the heat, but just wanted to point out there is a hypothetical future where the market could eliminate heat-wasted mining)