This is always a marketing strategy.
In local sweepstakes or lottery, TVs, radios, news paper will always cover for this in entertainment section, telling that "no one still get the jackpot price, it always grow day by day" that's  why many people will try their luck due to low risks with much price but witlh lower chance of winning.

On the digital world, a casino that has lots of promotions, lower house edge, lots of games always be the one who have lots of users while the risks will still the same, just depends on the games house edge and etc.