No, not directly but they do make money indirectly. A no deposit casino bonus is designed to draw new players to UK online casino sites and once you have registered and made your first deposit, the casino will start to make money but they do run the risk of losing money on players who just take the bonus, play and then leave the site and move on to the next one. Even though the casinos know that they will lose money on some of their no deposit bonus offers, they make far more than they lose and no deposit casino bonuses are extremely popular and still cheaper than conventional advertising.