Right, it happens all over the league. See: Jim Irsay shooting his wad all over Twitter because he was about to give a first round pick away for Trent Richardson.
I think there's this expectation that the consensus couldn't have been TOTALLY wrong when everyone agrees that this really high pick should have been an awesome player. It's an understandable impulse, one that I have fallen prey to also, but it turns a blind eye to the fact that there are top 10 picks every year that never turn into ****.
The best-case scenario for the league is something like the
2011 Draft, when 12 of the top 16 picks have already gone on to appear in at least one pro bowl. Even there, you have complete nonsense like Blaine Gabbert/Jake Locker/Christian Ponder all in the top 12 overall.