I also assume that it is true that everyone loses in the long run. You might get lucky a few times but if you keep playing, you will eventually lose.
Of course, that is the power of probability. It has been designed so that you will always be in the disadvantage.
In the most cases people are losing indeed in gambling and that is because the chance of winning in gambling is really hard and you need to be really lucky if you win some profit.
And people gamble and gamble until they become poor and that is bad because they dont realize it.