The sentiment here is that for the game industry Unions would be a benefit to put an end to unfair working conditions. Game companies have a lot of leverage because the demand for jobs in gaming for out weighs the supply.

Your bargaining power comes from leverage, and your only real leverage is that you can go work for some other company.

A labor union's bargaining power comes from numbers of it's members.

Certainly that can and has lead to abuse, but that is no different than what can happen with business.