Why do some private (even IT) companies not give a holiday on election day?Is this fair?

Private company not give holiday election. The government declares a public holiday for elections so citizens can vote. But I’ve seen even private and IT companies stay open or ask employees to use their own leave if they want to vote. Isn’t voting a basic right and responsibility? Why should employees use personal leave for a declared public holiday? Are companies indirectly discouraging civic participation? Or is this just “business needs” over everything else?