No, strike is a last resort.
They are paid a decent wage because they stick together and don't allow their employers to bully them and undervalue them, it's as simple as that. The train drivers don't look down their noses at the ticket collectors in the way that most private sector employees have been conditioned to do with their colleagues.
They have one of the best unions in the country and its been that way for as long as I can remember. They are a shining example of why everyone should be a union member.
If employees in other companies took similar strike action, their customers would simply go else where and the businesses would fail. So they would strike and have no jobs to go back to. That can't happen with the trains because they're subsidised and people will always have to go back to them. Do you get that? They have a captive audience and a monopoly.