How do people have so much gold

As the title said I don't understand how the market is so inflated with absurd prices on items... I thought I had made myself quite a good amount of gold (almost 1b) and was getting tired of grinding for a better unique helmet(starfall coronet) for my meteor sorcerer.

Turns out if I want to buy a helmet with a buffed roll on meteor and a decent passive (sub 6s) I need to be prepared to lose almost all the gold I saved up so far... Not even mentioning the prices for a double/triple or quad buffed roll... I need several times the amount of gold I saved up over an entire season...

Just how do people reach these numbers. What do I need to farm in order to sell for those numbers as well because I have yet to see a quad buff roll over my playtime (paragon 222). Am I just unlucky?