It's the manner of spoiling a vote or actively taking part. If only everyone who spoiled a vote actually voted. You never know. Say they all "wasted" their vote on the same outsider what then? Change.
You can never know if you spoil your vote.
Let's face it mate, if everyone that spoiled their ballot voted Green Party they aren't going to win over a seat are they?
Tubey said he votes in pro-Labour Kirkby so what difference is it him voting say Green or him letting his kid do it? You might not agree with the method but the outcome is all the same.