Depending on your opinion, they offer you the option of either playing with your money or playing a demo game for fun. I think it's a good option to see what the game is like. This is a marketing tactic, making players feel more comfortable. They'll play a demo game for a bit before playing for real money, get comfortable, and then, when they're ready, they'll invest their normal money and continue playing.

At the very least, they'll see how it works beforehand.