My argument is "I pay for plenty of music, why should I pay for everything I want to listen to?".

Unethical? Who decides that? Ethics is a matter of opinion, what one person finds unethical, another doesn't. I find the TV license unethical, and council tax. I think it's unethical that they put people in prison for growing weed. But someone who listens to music for free? Jesus Christ, you're a CRIMINAL. But those who make the laws, they're not criminals, are they?

Fuck ethics. When those is power are ethical, maybe there's an argument there.