While I certainly do see those species around, they're only venturing merchants or vagabond adventurers. In other words, they are segregated from society and can't hold a proper job.
"So, what are demi-humans and beastmen anyway?"
"Demi-humans closely resemble humans, yet they have defining non-human traits and features. Beastmen are even less humanoid than demi-humans. Oh yes."
"I see, so they belong in the same category."
"Correct. And since these demi-humans are thought to be closely related to monsters, they have trouble living in this nation. Therefore, they are often treated as slaves.