I think you've misread what we've told you. The possibility of injury or death was only if the man refused to marry a woman he'd impregnated out of wedlock. If he did what was expected, and married the woman, then aside from some hard feelings and perhaps public shame, he probably wouldn't be physically harmed.
Typically the offenders would be scared enough of the possibility of harm, that they'd do what was expected and get married to avoid the risk of what could happen if they didn't. The amount of times it actually resulted in violence would have been pretty rare for that very reason.
We've also just told you it's not nearly so common as it used to be. As to whether it's fair or acceptable - that depends on one's personal beliefs. Times change, and so do societal norms, as well as what's acceptable. You have to view such things through the lens of what was the norm at the time. The idea was that you had to accept responsibility for your actions. I don't see any contradiction in that, although the concept of personal responsibility does seem to be in decline.
You said it happens in your country, so why would it be any stranger that it used to be common in the United States?
