Why do Christians never practice what they preach when it comes to *peace* and *love for thy neighbors*?

How can you say "never" ? because to make such a claim you would have to know the mind of every single Christian on the Planet, do you? No you don't, All Christians fail to perfectly live up to the standard the Bible teaches. No Christian has ever been perfectly Christ-like. However, there are many Christians who are genuinely seeking to live the Christian life and are relying more and more on the Holy Spirit to convict, change, and empower them. There have been multitudes of Christians who have lived their lives free from scandal. No Christian is perfect, but making a mistake and failing to reach perfection in this life is not the same thing as being a hypocrite.

Peace comes when all follow the same laws.

Love is doing what is best for the other.

This is done well by Christians and they are the only ones who do it well. If you are discussing homosexuality (as usually this is behind such questions), peace cannot come to those who reject God and to love someone would be to make sure they knew they are wrong before God so they will change.

It's only "christians" who fail to do this you are implying? None of us are perfect - and all of us are who we are based on diverse factors, raising, experiences etc. SO we are all learning and growing in this life and it just takes each of us different TIMING to learn some lessons and realize certain flaws that need to change within us. Be patient with others - is what I've learned because we are ALL at different places on our path....

Matthew 5:18

For assuredly, I say to you, till heaven and earth pass away, one jot or one tittle will by no means pass from the law till all is fulfilled.

Apparently it's too much trouble. They'd rather just talk about it than actually do it.

You don't know every Christian. It's true, a lot of Christians aren't following the teaching of Christ, and many aren't true Christian. Please realize not all Christians are like this. Besides we're human, we make mistakes.

never say never. It takes a lot of maturity to practice what you preach, and i hope for all that are sincere well wishers that they will be also to do so rather sooner than later

Religious people are the biggest hypocrites in the world, no exception.

The bigotry, hate, persecution, and crimes-against-humanity they practice only applies when they do not hear their opinion in your voice.

Some do. But not many. And especially not fundamentalists.