I know I'm not taking the popular Christian view here, but I'm not certain gambling and lotteries are prohibited in scripture.
I will agree that we are to be responsible with our finances. We should act as good stewards of our possessions. However I see no problem with using your money for entertainment purposes. How many of you purchase movies, music, video games, sports tickets, etc.? Everyone uses there money for entertainment from time to time. If playing a game is entertaining to you and you're doing so in moderation- whats the big deal?
I'd also be curious to hear if those of you that are against lotteries and gambling also disapprove of investing money into the stock market? Would it be wrong to invest into a company? Are capital investments prohibited as well? I mean no return of finances is promised. It seems like glorified gambling to me. If we are going to take such a position against the lottery, then I think we should carry out such a view into the stock market.