Great point! We will test this concept in the future, some people want the convenience of a total package, others want to customize so they can "make do" and shave off some money somewhere.
Edit: Case in point. I was looking to get a Sparkfun Kit[1] but they were out of one item that made the whole "kit" out of stock. Down at the bottom they have a link to a "wish list"[2] that lists all the individual items in the kit. And a big button at the bottom of that page that says "add it all."