I don't think its feasible to think that Crawford is singularly responsible for protecting against pushing big market teams through -- he could only work one game of any particular series (other than maybe the NBA Finals) and the other guys could combine to officiate as many as 3 games in a series. I'd agree that Joey generally came off as more on the up-and-up than Bavetta (a notorious game manipulator), Rush (famous for asking the official scorer during a timeout how many fouls Shaq had), and Salvatore (the king of the FT shooting contest). But I also think that there are a number of other officials in the league who don't feel an obligation to favor teams or to manipulate games -- top-level officials like Bob Delaney, Dan Crawford, and Mike Callahan.
Like I say, though, I think if there is any truth to the conspiracy talk, as slayer intimates, the proof of that is most likely to come from a guy like Joey Crawford.