¿From where the 200pg/xp for level 2 standard comes from and how is it used?

I was searching for supplements for knave 2e and one of them I read was [this one](https://azorahaivii.itch.io/knave-2e-hacks-homebrew), where it was only needed 200gp to level up to level 2. this is something present on Many Rats on sticks and the tomb of the serpent king, and there should be a reason of it to exist.

so ¿from where it comes from?, which is the reason for its existence, ¿and how it is supposed to be used?