why casino is always profitable bcoz most people will lose and that is a true 
Casino's are always profitable even if somebody wins because the way casino plays they will let someone win and the other lose but their are plenty times for the losing part, and casino's tend to let you will at first but will let you lose on the end.
Casinos are not afraid of you winning their money but they are more afraid of you not betting with them. When you bet more often, you have a higher chance to lose with the house edge. This is one of the reason why casinos give you freebies to encourage you to return to bet.
Yes freebies are to induce the gambling addictions. I do see many people are making good profits in demo accounts and failing in real gambling. Same way when you bet in small amount you will win. When you go with bigger bet amount, no other go other than loss. Long run is just a theoretical, even in short run I faced losses.
Yes I'm also one of them facing losses from the first round of first day of gambling. But still I go for gambling with their faucet earning. I just gamble for analyzing the way how gambling works. May be in long run I may find my own way of making profits with gambling.
Everybody has their own reason for staying in gambling. Finding out a winning method must be a fake reason you are saying to your friends or spouse just to justify your gambling hours. Soon you will realize there is no viable method on gambling for profit making always.