There are distinctions we should consider when we apply the word *strange* to something. We often mean that it's odd or weird, but we should think about the other meaning of *strange*, as in "not from our area or experience." Most of any society's rules made sense at one time or another, but they might seem strange to us because we don't share the history or even the language to understand them.
We like to snicker at practices of the past. Our pastor yesterday talked about discovering that mustard was once used as a medicine (he's 31!), when he thought of it only as a condiment. Yes, it might sound strange now, but when it was all a person had, it probably seemed--might even have been--sensible.
I've heard people speak with disapproval at the Mideastern custom of many wives (not so prevalent these days anyway), but a society does what it must to protect itself. In cultures where many children die and there's plenty of space, polygamy can be a solution, providing lots of children so that a good number survive to adulthood. In island cultures, where space is limited, there might be polyandry, one wife with multiple husbands. She can only be pregnant by one man at a time, so it's a sort of population control mechanism. I'm guessing human sacrifice served the same purpose. First-born sons were popular choices, as were virgins. Both would remove a round of potential child-bearers from the group, upping the perceived value of the sacrifice as well as lessening the strain on the tribe's resources.
Even little things about any society are strange, but we seldom see them in ourselves, only in others. Women in our culture shave their legs but not their arms. Men can have their hair professionally cut and styled but don't accentuate their lashes with mascara. Americans are not into physical contact; any we have is stylized and brief. Other cultures show friendship by holding hands or walking arm in arm, but our inbred homophobia seems to come into play, or maybe it's our American independence: I walk alone!
In a thousand ways, the things we do every day seem strange to those who don't share our background. If we all thought about *strange* not as "weird" but more as "different from what I'm used to," we actually might all just get along.