While I can't take away your belief in a human right to something, I can take that something (given sufficient capacity for force). Belief in n/h rights can exist independently of whether or not the rights exist, in the same way that belief in Odin can exist independently of Odin himself.
Though, through morally-guided action you can possibly cause the n/h rights which you believe in (but which don't exist) to be reified as legal rights. Now, given sufficient capacity for force, I may still subvert those rights, but through their codification they have nonetheless gained existence.
The second part of your second paragraph actually closely matches my stance. And, it's precisely the prevalence of (implicit) absolutists who continually frame arguments founded on the assumption that some n/h right or another exists that leads to my irritation when these terms are used (relatively) carelessly. Such arguments are fundamentally flawed and, yet, continue to dominate most discussions concerning politics and economics.