RPG's: Some things I just don't get

I am a big fan of RPG's. That means "Role Playing Games" to the uninitiated. And, no, that's not the role-playing games in the bedroom (though, well, ahem, okay). It means video game RPG's--a la Dungeons & Dragons or Final Fantasy. GEEK ALERT!

This post will mean nothing to anyone who doesn't play video game RPG's, but here goes:

There are things that I don't understand about some of the "standards" of RPG's:

--Why does money weigh nothing? Some games have weight restrictions for its characters. But usually money weighs nothing. Do you mean I can carry around an 80 pound sword, but 30,000 gold pieces (or gil, or gp, or gol, or whatever the monetary unit is in the land) weigh nothing towards my total? I guess in every game, everyone has a "bag of infinite holding" for money. One example: Elder Scrolls: Morrowind. (Told you it was a geek alert!)

--The villains always seem astonished at being defeated by the hero. Why are villains astonished by being defated by the protagonist? (S)he always says: "How could you defeat me?" or something like that. Usually, it is the hero, along with his buddies who kills the boss. Just think about any street fight: when does a four-on-one result in the "one" beating the "four"? Only in RPG's.

--Are there any main characters who were studs to begin with? Why do all the stories involve farmboys who were dropped off at someones doorstep and must save the world through some cruel twist of fate? Don't any of these twists of fate happen to the best knight of the king, or any powerful wizards? Why is it just the teenage boys or girls?

--Why doesn't magic only hurt enemies? I've seen iceballs destroy entire rooms of enemies from the skies, but all my friends (or my "party") were okay.

There are more...I'll post them as I think of them...