Geez, there sure is a lot of complaining about a $20 attachment.
The Zapper at this point looks like an entirely optional piece of equipment, so you don't need to get it. Plus, even though the button placement isn't entirely lifelike or ideal, I think it's still beneficial for gamers that find the Wiimote too light and imprecise to aim accurately. (Example: the Haunted House shooting minigame in Super Paper Mario - I found myself trying to steady the Wiimote on my knee.)
And complaining about the pack-in game featuring a crossbow? Please. Since when is the Wiimote and Nunchuk an accruate representation of, well, anything? Besides, gun games are coming. (Ghost Squad, RE:UC, Medal of Honor).
If Nintendo released a "better" Zapper with more lifelike button placement, there's no way it would cost $20, and people would be griping about the cost of that.