Your doubt on viability is misplaced. A variety of ASIC miners are profitable with kwh prices are high are $0.12/kwh. The average electricity price in the US is less then this, with as low as about $0.08 in some locations. [1]

Small/medium mining operators just build in those cheapest locations.

The largest operations are turning towards purchasing or building their own capacity, some of which activity will still contribute to a supply/demand curve that raises prices for the entire country (or at least region). In some cases large mining companies have even recommissions old coal power plants, e.g., Marathon Digital Holdings w/ the Harding plant.