I don't know how people hired and paid by the government in place are automatically less suspicious than volunteers who just want to help the community. Yes, I have the opposite bias :)

In France the counting process is open and anyone can observe it and report any irregularity. Also the way it is done, you have to have a conspiracy of a least 6 people if you want to meddle the result.

In practice, I've observed that rather than fanatics, volunteers are usually mild people who are just doing the work as a nice sunday activity who doubles as a democratic tradition. They are the same people you see picking up trash or doing other menial work for the community. Of course, my sampling rate is quite low, so take that as a grain of salt.