Airport unions lack the organisation of their airline counterparts

The public is well acquainted with the regular array of airline strikes. But what of the airport sector? How does that compare with the airlines and air traffic controllers for industrial unrest?
It appears that a comparative lack of organisation, with many different roles being represented by multiple unions, means that bargaining and, when required, strike action are less coordinated. However, when different unions choose to work together and withdraw labour, the impact on the travelling public can be every bit as problematic as action by pilots, cabin crew and air traffic controllers.
Airport unions are especially dismayed by concession agreements, but they sometimes engage in the most unlikely campaigns.