I don't even bother to look at my iTunes sales anymore. I just assume it's 1/10 of my Amazon sales. But what is Amazon doing that is predatory? Genuinely curio

I don't even bother to look at my iTunes sales anymore. I just assume it's 1/10 of my Amazon sales. But what is Amazon doing that is predatory? Genuinely curious. Simply having a monopoly isn't a crime; abusing the advantage is.