Yes it is.
Public sector workers, paid by the state, pulling sickes are by definition taking money from the public purse to cover their “illness” when they get paid for the day off.
Private sector workers, paid by the private sector, pulling sickies are by definition taking money from their company’s accounts to cover their “illness” when they get paid for the day off.
Self-employed workers, paid or not as a result of their own hard graft and entrepeneuralism, don’t pull sickies if they can at all help it because not working = not getting paid.