This is similar to the "should Christians drink?" and "should Christian's smoke?" kinds of questions.
I think playing lottery is a question for each individual believer to answer like drinking or smoking. If it becomes a daily habit than I think it's an idol and then becomes sinful. But will I fault a brother for buying a lotto ticket? No, I can't judge like that.
I do not drink or smoke but will buy $5-$10 of lotto tickets if the jackpot becomes over $100 million. If I win, there will be many Christian organizations that would benefit with the winnings.
I think people need to be careful when judging others on this topic. Because I have meet several Christians that are strongly against gambling but invest money in the stock market via 401K which is gambling in itself. You can't have it both ways.