You posed the question of why there is so much "hate" when people try and justify their beliefs with faith.
The answer to your question is really quite simple: faith is the worst possible system for coming to knowledge.
Or, to put it another way, faith is the excuse people use when they don't have good reasons for believing the things they believe. To "have faith" is to be sincerely arrogant. This is not attribute anyone should ever seek.
I believe that what a person believes MATTERS. Because our beliefs are the gatekeepers of our actions - they directly inform how we behave. And if we want to put our good intentions to positive effect then we must have a good system for making determinations about reality.
There is not a single position - not a single belief - that can't be justified using "faith". And people use faith to justify all sorts of terrible ideas.
For example, when the daughter of Travis and Wenona Rossiter became sick they sincerely thought that prayer would cure their daughter (based upon James 5:15, Luke 8:50, etc.). They believed that taking her to the doctor would show a lack of faith. Unknown to them, their daughter had diabetes and after suffering two weeks in the most horrific agony she finally passed away.
Sadly, a simple shot of insulin would have saved her life.
It's not that the Rossiter's we bad people. It's just that they had a bad understanding of how reality works - because of faith.
And faith is used - sincerely - by millions of people to justify all sorts of horrible things. People use "faith" to try and suppress the rights of homosexuals. People use "faith" to try and suppress the rights of women. People use "faith" to try and suppress other people's religious beliefs and rights to freedom of speech.
If you care about the well-being of yourself and others, if you care about personal freedoms like speech, religion, equality, etc. then you have a solemn duty to try and believe as many true things - and as few false things - as possible. And you have a duty to have good metrics for discriminating between the two.
And therein lies the problem, because faith is the worst possible system for coming to knowledge. It can only ever be right by accident. And, all too often, the bad ideas it produces harms people in horrible ways. The Crusaders had "faith". The leaders of the Spanish Inquisition had "faith". And ISIS has "faith".
Far superior qualities are intellectual honesty, epistemic humility, and a desire to know what is true. These are the backbone of science and reason. To make sure that our preconceptions aren't misconceptions.
Where as faith - unjustified belief - is the exact opposite. It is arrogant, close minded, and dogmatic. It's directly responsible for some of the worst atrocities in human history - and is responsible for most of the current human rights violations going on today - and that, my friend, is why I HATE IT when people try and use faith to justify their beliefs.
-CL