Why so few names in the cast list?

There are more characters in the film than who is listed in the credits and we don't get to know who voiced those characters, like Larry, Blackwolf's mistress, or the fairy king. There's also some singular characters listed as Fairy and General but there are multiple fairies and generals in the movie those credited names could refer to. Why didn't they stretch out the cast in that case to distinguish the characters? There's a lot of people on the cast who were likely robbed of any acknowledgement for what they supplied to this rare chance in animation history.