At best, I've seen a few instances where very (very) small consulting firms may internally adhere to this and then just bill a client whatever they feel the appropriate amount(s) are for their work, split out into chunks of hours on invoices, so as to give the appearance to the clients that the billable model is in effect.
This is clearly fraud and worth suing and winning over. Charging standard "shop hours" like a mechanic, in advance, is one thing, but just making up a price afterward and pretending it was hours worked?
Billing client for reading internet, paper or chatting by the watercooler is also a fraud. Yet noone cares. As long as client is satisfied with results and the price everything else doesn't matter all that much.