I have a Newf/Lab so he wasn't on the list. I don't find it unfair if your dog truly is aggressive. But I think they should actually come out and meet the dog in question. How often do mastiffs attack as opposed to pitt bulls, German Shepherds? I guess they're worried your dog might not bite someone but that it could possibly flatten someone since it's so big?
I did find it unfair, though, that I couldn't run a meth lab or grow crops for cash in my backyard. I mean, hey, I own the place, don't I?