Sure you can save that €100+ for when you inevitable get cancer so you can go private to get cured. I am not and would not wish cancer on anyone but that is what you and every other smoker not to mention some unlucky passive smokers will end up with if you keep smoking. There is nothing good about it its disgusting and throwing cigarette butts on the ground is littering. Whats so hard about putting it in a cigarette tray or a bin if its safe to do so?
Mind your own business. What people do to their bodies is their business, not yours.