I hate religion for its brainwashing. "Hate" might be too strong a word, let's say "strongly disapprove".
To be honest, I don't care particularly, if god exists, or if other people believe that god exists. There were a lot of good people who were religious and did no harm. However, in modern world there are still trials (Pussy Riot in Russia, numerous Sharia trials in islamic countries) or killings happening as a consequence of cultivating religion. I think this is a perfectly valid reason to dislike religion as institution.
But again, that's not exclusive to religion.
No, just pointing out two things:
1) In the marketplace of ideas, ideas that work should be able to outcompete ideas that don't work.
2) In the modern world (as opposed to the ancient world), religion's purpose is to keep that from happening.