It's really simple. People with "unusual" behaviors (meaning, relatively unusual to society's current conventions) have an unique combination of environmental and neurological factors that make them the way they are. From a biological evolutionary standpoint, not social one mind you, there is absolutely nothing wrong with them; however, our social standards have changed faster than biological evolution was able to keep up - this leads to incongruities between what is socially acceptable and the hard cold reality of the molecular machine of the human body.
We are on the cusp of gaining the capability to close the gap between these two realities via gene therapeutics, biotechnology, genome sequencing, cloning, et cetera. As there is no objective right and wrong in the turnings and goings of biological evolution - it has no endgame, no ultimate goal but we enlightened ones know that already - there is no absolute moral authority existing anywhere in the Universe to prevent us from giving people with "mental aberrations" a chance to be treated and be accepted by society at large. Caveat though, it is equally true for those who think these people deserve to rot in psych wards and prisons, or in some cases, get on the death row.