For me in Australia the game is $100 and I have 2 other family members who want to play as well (multiplayer). That would be $300. Should there be some kind of family discount bundle (on steam) where you get 3 or 5 keys?
Not sure it is a good idea, people will start selling acount, whit game, at a lower price. It will hurt badly the developper income.
I understand you got a family, but i am also father of a family, whit a similar problem.
For now, it is every one that share the same computer and the same game.
When they start working, they will be able to pay their own games and computer.
Just buy the keys on some other site like mmoga. Its usually around 15% cheaper there. The price there is about 50 €.