Well, casino is a business. Business is for profit, so of course there needs to be money going in, more than going out (otherwise, you're broke). It thus makes sense for the house to be at an advantage, and for people to lose more [often] than they win. It's natural, and it makes sense. Gambling is an entertainment, and people pay to be entertained. In this sense, it's not losing money, it's paying for an experience, for the thrill, for a chance to win.