I don't disagree, but as someone who uses T-Mobile, the only thing they have going for them is their cheap prices and freebies. And even then they're barely worth it. If prices rise their customer base will disappear.

I am also a T-Mobile customer, but more companies is better even if don't use them. For me paying few dollars more is nothing and we get priority on the T-Mobile network. However, some people might really need that few dollars, few bucks here and there add up.