Keeping track deters the bad habits from getting over and indeed is helpful for people who think they are losing it because of the gambling habits. Just seeing how much one person can save from not gambling is often enough to stop them from gambling anymore.
In the long term, it will help people to cut down their spending on gambling.
It’s really not fun keeping logs if you’re not serious about gambling. I believe that kind of effort is only for pros or those aiming to go pro. so it’s understandable why some people don’t bother with it as it just feels like extra work. As long as they gamble responsibly, even if they lose, that should be fine.