I sold a used 268 comp cam for $20.00 years ago to a friend and he installed it in his engine with new lifters and ran it no problems. As far as I know that engine is still together.

I wonder if there was some way the cam companies couldn't do a break-in before selling them? Make up some sort of machine that replicates the top half of an engine that runs off an electric motor for 20 minutes while motor oil is being recirculated over the moving parts. I bet people would pay more for a cam that was ready to go, or closer to it. So long as the lifters spin free in the customers block it seems like there would be a little less to worry about.