Election time again

We're coming up to another election, and so it's time for a look inside my postbag again. Tonight I have two leaflets delivered together: one is from the Scottish Lib Dems, and the other is a virulent tirade against AV, from people calling themselves no2av. Oddly, the Lib Dems don't ask me to support AV in their leaflet. Why is it that the no2avites can get to use the electoral register (the letter is addressed to me personally)?