People need their vegetables for a healthy diet so it should come as no surprise that cats need their greens too. That’s why cats often munch on grass so they can hurl it up when they come inside and mess up your expensive carpet.
Still, cats eat grass not just to gross you out, but because they may get nutrients from the grass or fiber to help them clear out their system. Then again, cats might eat grass just to mystify humans and keep us ignorant on their true motives.