In theory, unlimited access to alchemical ingredients didn't necessarily mean that a disciple could seize them all, far from that, actually.
Even in the face of privileges, cultivators were supposed to show restraint to avoid their greed from affecting their reputation and ruining their image.
Taking the Sect into consideration was also important. Cultivators had to be wary not to go overboard to avoid angering the very entity providing that privilege.
Moreover, respecting certain limits would demonstrate a demeanor suitable for leadership. It could basically be a test of a cultivator's character, which Liam failed.
It wasn't that Liam didn't realize the potential repercussions. He definitely couldn't consider them all, but that was beside the point. The Sect was using him, so he felt completely justified in getting as much as he could from it. It was only fair.
