Gambling is a fun activity done consciously by the gambler, no one forces you to do it, it's a personal decision made by those who engage in it. Gambling is only a scam when you get defrauded by a casino or sportsbook. A friend of mine told me about how his account got swiped by a scam casino. According to his story he said that he put in his card details to deposit money, after doing that he started noticing that he was being debited by an anonymous source constantly, he had to transfer the money he had left to another account, in this case you can call it a scam. No one is promising you a win, it's 50/50 and everyone is aware of this risk before placing a bet.
It is true that gambling itself is not a scam if it is conducted in a fair manner. However, in your example with your friend, we are talking about a clear scam on the part of the casino, which may be due to the insecurity and unreliability of some platforms.
Many of us gamblers believe that gambling is not a scam, although there are some casinos that operate illegally that end up being scams. But if it is regulated, the chances are high that it is not a scam.
We just have to know how to investigate or choose casinos whether they are legitimate or not, because if we have no idea, we will surely fall into the trap of casino scams.
If we talk about it from this point of view, it is not so difficult to determine the type of casino, especially if it is a physical casino, because it is very difficult and almost unrealistic to open an illegal casino in cities and anywhere else. With online casinos is much more difficult, you will have to seriously search for information on the Internet itself and there is a high chance of not finding it, no matter what the casino actually was.