Getting rid of unions in the airline industry will be next to impossible. Any situation where you have a skilled labor force that doesn't really have room for vertical movement (you can't really become a better pilot with age, at least as far as the job qualifications go). Much like a coal miner, there isn't anything stopping a company from continuously bringing in new workers at rock bottom wages. Plus there's the fact that aviation is a romantic industry, people are willing to work for subpar wages jut because it's the airlines. Lastly, as much as the airlines spout "safety first" and all that, they really don't follow through. When the going gets tough, don't think for a second that they will not intimidate pilots to fly beyond their means whether its sick, tired, or sick and tired. After all, there will ALWAYS be plenty of people willing to take your place and not stand up for safety.
So to wrap it up, as much as we like to blame the unions for all that is wrong with the world, and they do deserve quite a bit of it, it's a necessary evil for our business. As someone who has seen the other side of this (Part 135 charter) I can attest that not having the legal collective representation of a union, you will be abused. Just the way it works.