Why must people be so judgemental of other's religions?

I was raised in the Catholic faith, but now i am in my later teenage years and I am starting to lean away towards this faith. The ideals of the faith are great, but i believe that they are symbolic. I have my own beliefs that are a mix between Buddhism and Judaism.. I told some of my friends about a few got very upset. People started to find out and criticize me. I'm not atheist, im just sorta skeptic. Why would people of a religion that is supposed to respect all people be so judge mental?