I think what a lot of people are forgetting here is that the ones who will make the decision about anything are shareholders. All shareholders want is as much money as possible, so when you ask them "will you give a cut of each games profit to these voice actors", the first question they will ask is "can you replace them?".
The industry is the way it is because shareholders demand large profits as fast as possible. If they could release 5 games a year in the same franchise they would do (see sonic as a good example of franchise self destruction). They are not going to accept losing anything on their dividend without good reason. I'd love if most developers and people who work on games in a core role got something from the games sales as well as better working conditions, but as long as these are publicly traded companies, chances of it happening are next to zero. We're in an age when a series creator is seen as replaceable when they complain their creation is being mined to within an inch of it's life. Everyone is replaceable in games, even the guys who created COD, assassin's creed and MGS. I do not see this going the way that the unions think it will.
There is option B though, a company I worked at years back had a strike over temporary workers getting more pay, all my boss did was signed the union contract as a stopgap and then didn't hire unionised employees again, they got their cash short term but after that were unemployable. I remember him saying 'there is a saying in the east: short term profit at long term cost'. He changed company contracts which locked out any one who was a member of a union from getting a job at his company.
Another good example of this is Murdoch, during the 80s workers kept going on strike at his printing facility for UK paper The Sun, he built a new plant over a year, hired new workers with different contracts and went into the old plant one day and told everyone they were fired.
