Acceptable? No. Realistic? Yes. Its not acceptable that it costs a tenth of my annual salary to fly to Australia. It is, however, realistic and I'm bloody well stuck with it, yeah?
They have no possible reason to open source the game. As it stands, it may not be making THEM money, but its not making anyone else money either. Its not providing a template for wannabe game makers to provide competition. They will continue to sit on it.
Further, the property will never come up for sale, since the parent company of Interplay will continue to own/hold copyrights, trademarks and patents for any Interplay property, even should Interplay be dismantled. Isn't the parent company Titus? A historically greedy company?
So, again, give up. It won't happen. Sierra is more likely to opensource ITF.