You talk about characters having every skill as if it were a bad thing, Henry. Consider Conan, the 20th level Barbarian. He's seen things that would drive most men mad; he's been around the known world, fighting Lovecraftian horrors, and he's seen wizards and warlocks do some pretty crazy stuff with magic. He has a Spellcraft of +10.
Take your 1st level Wizard. He has a +10 Spellcraft (if he is focused), plus his Intelligence modifier. Now consider a conversation between the two, considering amiable circumstances.
"How do you know of a wall of force, you big dumb barbarian?"
"I've seen my friend Pelius cast such a spell before; it was also used against me by a dark wizard from Stygia. Nothing can penetrate it; it is immune to being breached."
"Yes, well ... I have read alot about it, and that seems to be the trick of it."
You see, level is the difference between knowledge and experience. Conan experienced it, and the wizard knows of it. It's all about interpretation of the character.
Like someone else in this thread said, Conan can't use the trained only functions of the skill. I assume every group has some downtime between adventures, allowing them to persue other skills of interest. It isn't too unrealistic to think that a 20th level character has picked up a little of everything; especially Conan, who has done a little of everything.
EDIT: Aww nuts, someone already posted an example similar to mine. I've been scooped!