[Morromist]

As an american voter I confess you're right.

- but also there aren't many good alternatives for us. Say you have 3 people running for senate to choose from. Canidate A and B have super PACs that spend $80 million each on ads. Canidate C doesn't. You could vote for canidate C, but he will likely lose - nobody sees anything about them, they can't employ many people to work their campaign, they don't get interviewed on tv. It feels better to vote for someone who has a chance to win. Also candiate A is a nutjob who thinks we should take over Tierra del Fuego as our 51st state and all young boys should have a year where their schooling is just learning how to throw knives really good like a Ninja, so you really want them to lose - you pretty much have to vote for Canidate B.

[SAI_Peregrinus]

Also the official presidential debates are a privately run event, not a public thing open to all candidates. The president isn't the only politician, but it exemplifies the problem that our election campaigns are privatized.

[foxglacier]

But why not vote for a loser? Is it just some irrational pride/feeling thing? One vote is never going to determine the outcome anyway, yet a spoiler vote is still a signal to A and B about how competition is stealing their votes and how they could win you back.

That other reason you mentioned is ridiculous too. Since parties A and B always win, alternating each one or two cycles, it's not the end of the world if your hated one wins this time - if they don't, they'll just win next time anyway.