At the very beginning of the Universal Recommendation for Right Zazen Dogen tells us that this sitting is to return to the original source in penetrating purity and freedom right here and now. We stop all karmas which drive us to delusion, attachment, and aversion; me-ism, materialism, and militarism; fame and fortune which create all kinds of problems.
Presidents of countries or companies are great gains, we think, but commit crimes of wars, exploitation, extinction, etc. We become enslaved by power and matter. However, when we sit and stop karmas, we are not anymore enslaved by gain and loss, birth and death, and reach unconditioned peace and unsurpassed awakening. This is the merit of zazen.