Wow. Your view of a country's government and it's responsibilities is so so sooooooo narrow.
You have a right to vote as you please....in this case...on a very very very insignificant topic. But go ahead.
No, it isn't narrow.
In the big picture, voting against Harper even if on this issue, could mean that he doesn't win by much, or loses more seats.
If the view is that having a Harper majority government is not in the best interests of the people of Canada, then being a single-issue advocate is a means to that end.
(I used to criticize single-issue advocates, but now I see that there is a place for them in a democracy, as has always been the case).