I don't like people having a pop at officials. Not from any puritanical standpoint. Just, well, they ref at non league level cos they're a bit poo. Much like the players. And with that in mind they are going to get some decisions wrong.
That said, it also possible that they get the odd decision wrong solely to wind up the obligatory angry mad bloke who appears to frequent pretty much every non league game you go to.
Exhibit A (unless poor football on a poor pitch in poor conditions is your thing, fast forward to about the 5 minute mark) Including rubbish fighting, rubbish defending and rubbish decisions from the men in black)
Huge props to the recently discovered Cold Tuesday Evenings blog for the find.