Because it tells us to do that in the book that advocates slavery acceptance, misogyny and homophobia... you're really not addressing the issue here. I know which bits you want people to focus on - the 'nice' bits - but why should I accept those bits and overlook the other bits, other than by making my own moral judgements which I can do without the mythology and superstition?
O.
There is alas for your argument, things which don't apply to me.
There is an instance of God showing who laws apply to and who they don't in the vision of St Peter.
You sound then if you need reminding about the division of the Bible into the Law, the prophets, poetry and proverb and that's the Old testament, and then there is the new testament.
Collectively the OT and New Testament is information needed for Salvation since the laws themselves do not save.
So I am not compelled to hate those who hate me, I am not compelled to settle for slavery or misogyny or to hate those who hate me, in fact the opposite. I think I have said before the least we need,imho to remain of the Bible is the part that says we need salvation and Jesus provides it and at the end of the day it's that, that really offends people.