The fortune teller wasn't always at the Ji Ming Temple offering readings, only sometimes.
He had just received a message from Xiao Feng, and to his surprise, Zhang Wei had fallen ill again!
As far as the fortune teller's own knowledge went, he understood a bit about "The Book of Changes" and thus a bit about divination, but whether his readings were accurate, he himself wasn't sure—it was all probabilistic.
Last time, he managed to get a sum of money from Zhang Dongliang and his wife, effectively swindling them, as cheating wealthy people like them was his favorite pastime. If it were just about setting up a stall and reading fortunes, a hundred a time wouldn't add up to much in a day; in his eyes, that was hardly enough to afford a luxury house or car.
However, conning the rich was a different story, as he could make tens of thousands, even hundreds of thousands, at a time.