This is to remind us that gambling is all just about luck. It's just ironic to see that those who dedicate most of their time on gambling rarely wins. But those who just bets on a lottery occasionally are blessed by luck to have a chance to change their life.
These news are only to remind you of your own addiction to play. 
They want nothing but their old players to come back and bust their winning in the same casino. These are marketing methods to manipulate greedy players and new players into joining a site for playing. I am more than assured that the news are paid by the casino owners. Winning a lottery does sound tempting to try out but there is no guarantee that you will be the next big winner. In fact you may never win at all and keep on buying tickets.