In my experience all these knife companies have slightly different bussiness models. For example Benchmade has a pretty hefty price tag on their knives but should you break a pocket clip they'll send one out no charge. Spyderco on the other hand prices thier knives more reasonable and should you need a new clip one will be shipped for a modest fee. So when you get right down to the nut cuttin , when all's said and done it's a wash.
See, it was this line of thought that prompted my post. The more the cost of the knife, the less you should have to pay, if anything, for replacement components, especially if lost through a defect or QC issue.