> your expenses will ALWAYS somewhow expand to your income

No they don't. This may be true for some people but many people do not have this compulsion. I know many people who have zero issues saving money because they are largely satisfied with their lifestyle.

The lifestyle doesn't even have to be austere. You can eat out every night at nice restaurants and rent a very nice place on a budget of a couple hundred thousand per year. There is a natural limit on the amount of money you can spend unless you are blowing it on lots of expensive "stuff" that contributes relatively little to quality of life.