The Five Angry Wizards were VERY angry indeed. How could Slytherin have triumphed over the champions of Gryffindor, Hufflepuff, Ravenclaw and... er.... Babbagin and Turington.
I'll tell ye how: most of the voters will have been exactly the sort of non-Wizard bean counters who joined the B"C"S in the past couple of years and turned it into an offshoot of the MBA Old Boys network, i.e. the people that were attracted by the very changes that the Wizards are protesting against.
In short, the Five Angry Wizards asked these noobs to vote to turn the BCS back into the sort of society that they'd never have joined in the first place.
Still, at least that basic FAIL in understanding illogical hew-man motiations demonstrates their status as *true* Wizards. Doubtless they'll respond with a rant about how the membership must have not failed to discomprehend that they weren't voting to unchange the opposite of the status quo.