This isn’t how it is. But it’s how they see it. Again, this is from their point of view. Or at least, it’s what I heard from them.
Capitalism is about self reliance, “pulling yourself up by bootstraps”, getting out there and making your own way with no higher power (as in humans) standing in your way. They see socialism as a government forcing people to give up their own hard earned gains to give to others. The difference with Christianity is because God is telling them to do it. If God tells you to go feed the poor, then it’s OK. If you choose to do it yourself, then it’s also fine. If the government wants to do it without promoting their religion, then it’s bad. Because you’re not doing it for God.