Gambling is supposed to be a game of fun but unfortunately a lot of persons take it to be a source of finance which is logically wrong. Yes gambling arguably can be tempting to be a source of income especially when you tend to make multiple wins consecutively which could make one feel the need to take more days off work since you have become richer at an easier pace. The core reason people should not take gambling as a financial source is because people tend to be very serious when it comes to their finance which of course us their main income source.
Now if gambling becomes a source of income you will tend to gamble more so logically you could win more and most of the time this could end badly and even lead to a nasty addiction in some cases.
Not lot of person,almost all the people use the gambling for making entertainment.The first thing need to understand is the gambler should betting based on the wallet,but many gamblers bet above their holding with the overconfidence.If the algorithm of the gambling site was changed the entire money will be leads to the loss.The gamblers who want to make money should use of the small and reasonable betting based on the holding money.Gradually increase your wallet balance will able to keep the strong wallet.If you increase your wallet by making the random betting money,the same money will be loss from the random money betting.
I think you or we cannot rule out the fact that actually happens in gambling where most people or gamblers make gambling a place to earn, or simply they always prioritize winning in every bet, I understand that whoever it is that even though they come just for entertainment but still they will never refuse the name of victory but maybe the difference is that there are some gamblers who are too pushy to win and there are also those who wait with patience and maybe you also already know the two types of gamblers that I mentioned.
On the other hand of course what else you said is true about betting according to our abilities or meaning not overdoing it and only spending money that we can afford to lose because this is the approach that is always recommended in gambling which is full of uncertainties, and I think it is an inappropriate idea to say or allow anyone to bring the idea of earning in gambling, even if you only bring a small amount but still the mindset of "earning" should be avoided because I am sure that over time they will think of increasing the amount of bets in order to make bigger winnings, and so it is more appropriate to simply think that gambling is only for fun and limit all your gambling activities.