Of course gambling isn’t a scam. Obviously there’s a house edge but gambling is a huge business these days, there are casinos and sportsbooks (both physical and online) all over the world. Most are highly regulated and run lawful and obviously very successful operations.
Calling gambling a scam sounds like the words of a degenerate gambler who can’t take responsibility for his or her own actions. Most casinos & sportsbooks push responsible gambling on their punters and offer self exclusion limits. Gambling as an industry is not a scam at all.
I agree with you that players who say that gambling is a scam are not very smart, maybe they are just sad because of losing, although if they won, they would never say so. Now there are many materials and forums where you can read a lot of information about gambling and fully understand how it works. I usually study the topic, and therefore move on to practice, and not vice versa, so I will never say that gambling is a scam. Casinos, bets, poker, do they give us a chance to win, and of course we try and will most likely lose more often, but this does not mean that you can’t win in it, it is important to learn to understand the risks and be a competent player.
True, when a gambler gambles and wins he gets paid his potential win and so it is not proper to call gambling a scam. If gamblers are denied winning when they win or the game is such that there can be no winner then it can be called a scam. In gambling, people win and people lose. If you make the right prediction you can win. Personally, there are times I have a good run of winnings and never have I been denied my payoff. However, the fact that gambling is not a scam doesn't give gamblers license to gamble without control. It is difficult to win in gambling and so the bookies are always benefiting from the gamblers and so the onus is on the gambler to gamble wisely in order not to be a victim of financial, mental and emotional ruin.