This is a Role Playing System, it does not affect Adventuring Wealth
The the WBL guidelines, as always, controls Adventuring Wealth, nor do the Campaign Rules make it easier for Crafters to create lots of extra adventuring items, PCs still follow the standard rules for that. However, it provides ways to interact with the world, in a way that can meet a PC's personal goals. If the PC wants to be Baron Boomtown, these rules will help, If they want to live in a Palace, or have the ear of kings - these rules can do that as well.
All of my game setting encourage PCs to interact with the world as part of their role playing, and the campaign system facilitates that. There are lands to conquer, titles to claim, businesses to build, fortunes to make, etc. The campaign system gives me a framework to manage that across my game settings. PCs don't have to engage with it, and the game should work just as well without it. It just depends on how you see your playing of role-play style. However, there is a reward, even if only a small one. Use the campaign system well, and it will pay you Monthly Cost of Living Expenses for you :)
It is based on This Economic Overview - This is mainly of interest to me, as a world builder, and hardly affects PCs at all. The economy has always been a bit broken in RPGs, this puts in some sort of perspective for me, and underpins the rest of the system.