That reading gives the capacity to gain a better understanding, doesn't mean that all readers use it that way. The act of reading itself doesn't make the people more willing to be more understanding. Someone who cannot read could have the same desire for understanding and might choose to engage that desire by talking to people in person. The fact that the latter doesn't read, doesn't make him less morally superior.
The only correlation that reading and intelligence have is that intelligent people find it easier to read, and therefore enjoy reading more, and therefore read more. It's not the other way around.