We vote so we can choose our president. Without a president there would be no government. Another reason is there would be no laws to keep up with. Also there would be no structure to our community. With a president everybody is safe and follow the laws where no one gets hurt.
With president we have governments. Without government there is no laws. Without government people won't follow the rules and won't pay taxes. Taxes is also important. Taxes pays for water, electricity,