General Discussion

The cost of stealing all that human labor and creativity for "training"
The cost of using up rivers of cooling water. This winds up on municipal water bills.
The cost of burning gigaWatts of power. This winds up in utility customers' electricity bills.

The are other more subtle costs, like degrading human minds. Or surveillance in fief to profit and political power.

When you disperse and diffuse costs, it's hard or impossible to invoice them.