Kureha is devoted to the kingdom and the heroes aren't going to be advertising that they are abusing one of their own.
I think it makes sense that they look down on a healer. It's a corrupt society that values strength. Loosing and needing help is a sign of weakness and everyone other than yourself is replaceable. Even other heroes since when they die someone else gets chosen. A healer has no offensive capability and can be replaced by a stock of potions.