The Universal Declaration of Human Rights, though not international or domestic law, affirms an individual's right to concepts like "dignity, liberty, equality," freedom of "opinion, religion and conscience," and even "economic, social and cultural rights," including healthcare. Yet, human lives matter differently to different people.
Living in the Western world, it's more common that each person is perceived as a diamond in the rough, full of unmarked potential. This even extends to ever-so innocent animals. I know people who exhibit a near-reverence to animals or harbor a dislike towards eating animals in the form that suggests their body shape. Or refuse to acknowledge the sight of animals eating other animals. Even popular now is this article saying that plants have feelings, too.
Furthermore, the line between what is a human is a subject of much controversy. Sometimes in the 1990s, a controversial version of IVF took place, called 3-parent babies. Parental DNA (minus the faulty disease-causing mitochondrial DNA of the mother) combined with mitochondrial DNA of a third-party donor caused quite a stir. Shortly afterwards, in America at least, phrases like cannibalization of one embryo or sacrifice one to help another (even though the sacrifice was an unfertilized egg) inundated the news cycle.
I think that if everyone could afford the luxury to care about every other living being, the world would be a more peaceful place. Intrinsically, I believe humans tend toward peace, but maybe one of the many reasons why lives have different values to different people is economics.
There have been several ways we've placed monetary value on others, with consequences. In other places in the world, you hear of concepts like hit-to-kill, where laws on victim compensation incentivizes a driver to pay less to kill a pedestrian than to cripple a person and fund their medical treatment for life. Ethnic minorities, often with less economic power and perceived as possessing less intrinsic worth, are being slaughtered in various countries. In personal injury lawsuits, the loss of earning capacity payout is proportional to the plaintiff's income level, suggesting the difference in monetary value of a CEO vs. a homeless man. A challenge in the world is educating a culture that divests monetary value from inherent value.
Rather than passing value judgments on those who regard human life as worth less, it helps to understand that some people are born into conditions where every life decision is necessarily contingent on economics.