Sure. Any time someone tries harder it affects the people they're competing with. But should that be illegal?
When they are unnecessarily exceeding the requirements of their job and thereby negatively impacting those of us who are doing our jobs as they were intended.
They might find their car damaged, or their face.
Yet more proof that unions are domestic terrorist groups and should be dealt with as such. Shoot a few hundred union goons and the rest will probably smarten up.