They know it will work because it has worked before. They probably make the demo look as if you can actually win and let you enjoy that thrill until you get so invested to want to play with your own money. Once you do, you don’t win as much as you did during the demo games.
The demo is just like playing a regular game without the pressure and challenges, but it's illusory and designed to be easy and doesn't require much thought. What you said above is true, and it's very different when you actually play it and make a deposit. For new players, there are usually a lot of surprises at first, as they bet small amounts. When they bet large amounts, this is where their game begins, a war of nerves with the dealer. Can we easily defeat them
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