You're still satisfying your ego knowing you've done well for your God. You've also made yourself comfortable knowing you'll have peace after death. The bible doesn't make morali judgement altruistic.
I wish the bible only boiled down to "dont be an asshole" .... I might still be religious.
If the Bible was the sole thing Christianity was about, every Christian would be a Baptist.
Traditional yet scientifically accurate understanding of St Paul's Church, as well as understanding that the Bible, regardless of its divine influence, is a bunch of different texts written by different people at different eras with different audiences, are major components of Catholicism, which is the biggest Christian sect in the world.
OT showcases God as being either Yaweh or El and being really nice to Abraham, to being purely Yaweh the angry and jealous god of war, to being angry at the Israelites and preaching the tolerant, loving, moral aspects of the Torah over the more warfare-based ones (although it still led to a tribal interpretation). The NT goes and practically retcons God's violent nature by showcasing Jesus as an extremely self-sacrificial, loving, tolerant person.
Either way the gospels are the very basis of Christianity, so yeah...
Also, the point of Christian charity isn't to pat yourself on the head for doing what God wants but to be an extension of Jesus' actions. Hence why the Church is considered to be the Body of Christ.
Whether you consider it to be mere depersonalization or truly something higher, you can't deny it's not the same thing as masturbating your ego because you're being God's pet. The point of Christianity is not to feel nice but to do nice.
Now, there's the question of how Christians actually act, be they Catholic, Protestant, Orthodox or something else... I mean, how many drug lords, gang members and hedonists are Catholics?
But the core of the faith isn't very arguable. The way the Church re-interprets them as culture changes, and the way believers actually act, are.