BDSM: I don’t get it

The raw and visual depiction in movies like 50 shades of grey or Secretary does celebrate and promote the strange lifestyle of BDSM (Bondage, Domination, Sadism, Masochism), but do they hold any merits?
Is BDSM a deviant or kink that occurs with a section of the society or is it a mental disorder? Is it a threat to the society? The difference being one is some idiosyncrasies that others (esp. your partner) can accommodate while some are illness that needs to be cured before they go out of hand.
Let me ask you a couple of questions:

  1. Psyche of a BDSM practitioner
    1. Would you like to be friends with anybody who likes to humiliate abuse or even torture fellow human beings for no grudge but pleasure?
    2. Will you trust a submissive that enjoys being kicked, verbally assaulted or worse on a regular basis?
    3. If your kid shows traits of being a Dom or Sub, will you not seek professional counsel?
  2. Safe and consensual
    1. Personal bias aside, there is a thin line between being brainwashed and consensual. Several charismatic cult leaders have steers their followers into mass suicide inside churches/synagogue. Many of them have steered into heinous crimes. Do you think BDSM is a safe haven for them to hone their skills?
    2. As a medical professional, law enforcer or a healthcare worker you discover spousal abuse, domestic violence or any odd behavior. Will your conscious allow the perpetrator to hide behind consensual cover?
    3. Take a reverse case, how will you prove the innocence of a dom whose sub (for vengeance or foolishness or simple play) recants on the consensual BDSM statement? How will you investigate the fact of the matter?
  3. Behind closed doors
    1. Voyeurism, exhibitionism, role play are favorite terms of a BDSM scene. This means that unwitting passerby often gets involved into the act. Are adequate precautions taken to protect a young mind at an impressionable age?
    2. Wearing skimpy clothes, being treated as a pet/slave in public, open display of ownership marks (branding, tattoo, chains, collars etc.) is often not behind closed doors
    3. One of the leading banks in Amsterdam bank did fire a bank audit officer who moon-shined as a Dominatrix. Their rationale was that leading a secret double life will expose the lady officer to blackmail or actions that compromises the integrity of her desk.
  4. Social cost
    1. Do you think government/NGO should cover the cost of treatment of medical injuries sustained during a session?
    2. Who should pay for the cost of rehabilitation of someone who wants to move away from an abusive relationship?
    3. Should insurance cover the cost of treatment of a fire/amputation/mishap
  5. Sub rights
    1. Being pierced, forced into unsanitary actions, branded, tattooed and various other BDSM activities have a potential medical risk. The sub can be permanently scarred due to this.
    2. What is your recourse to a dominant who does not honor the safe-word or pushes you too much?
    3. Who is responsible for the irreparable damage due to food/water deprecation, confinement, no flow circulation due to prolonged bondage, not setting the voltage in electrical wand, tearing of tissues/genitalia
    4. No equation remains the same forever. Is the sub able to cope up with the separation/demise of the dom or power center of the relationship

A little bit of control, power games, fantasy is needed to spice up the relationship but excess of anything is dangerous. I am strongly of the opinion that “The government has no business what happens behind closed doors between two consenting adults”. But is the BDSM practice really compartmentalized that well?