I agree it would be a useful feature, actually. Same with the avatars, "Polo's Avatar" is not very helpful. But with the avatars, you can right-click and check the url for the image. Of course, clicking a mascot to find out its name is a lot easier than that... and if you don't want to read the whole bio, you don't have to. The character's name is spelled out for you, both in the article, in the address bar and the browser tab and main window headers.
EDIT: Ok, not in the address bar, apparently.