There's dozens of mobile providers. What kind of "bs" are they pulling that you'd want to boycott them all? I had several in the US, and all the smaller ones

There's dozens of mobile providers. What kind of "bs" are they pulling that you'd want to boycott them all? I had several in the US, and all the smaller ones (MVNOs) were fine: they did exactly what they claimed as far as billing and level of service. The only reason I left any of them was because I found better network coverage, or moved. I honestly don't understand why you'd want to support a company that treats you poorly when you have SO many alternatives.