Luckily there are more than just 2 parties to vote for... true, the PC and Liberals were the top dogs but the oft-overlooked NDP certainly bumped things up last time and the Green - well, they were given a seat off in the backwaters of BC... oh, and a few other regional/sort-of-national parties as well - there are alternatives if you're willing to test them out.

Well yes and no. Imho, a vote for anything other than the two who can actually win is as good as no vote at all.

Sometimes I think they are put there by the main parties to steal votes from their opposition on issues they cannot possibly accommodate.

that's the exact intention of attack ads, they disenfranchise voters, and this is usually very good for incumbents.