One major reason for this is that the load for these users is usually constant and predictable. The load at a fast charging station would necessarily be spiky a

One major reason for this is that the load for these users is usually constant and predictable. The load at a fast charging station would necessarily be spiky and most likely bimodal (going to/from work, I'd imagine), so their cost wouldn't go down as much as, say, a steel forge with massive arc furnaces.