What's The Difference Between A High-Risk Customer And A Victim?

Scenario: An obese woman pays more for health insurance than her slimmer neighbor because the insurance company deems her a "higher-risk" customer.  

Most people can get behind the basic idea of this, right?  Scientific studies have proven that being overweight makes a person more susceptible to a variety of health problems, blah de blah blah.  If the company has to put out more money on behalf of someone because they're going to be at the hospital more often and will go through more expensive procedures than other people, it makes sense, right?

Except that you can't guarantee that this person will ever go to the hospital for such a condition.  In which case, she's just paying more because she's heavier.

Same deal with someone who smokes or becomes an alcoholic.  Statistics prove they're more likely to cost a lot of money in medical bills, but the individual circumstance could vary with anything from liver and lung cancer to a doctor-free remainder of a lifetime.

Then let's consider the same scenario but in a slightly different context: what if a person suffers from a preexisting condition?  Say that instead of smoking, you have a history of heart disease in your family.  It wasn't your choice, but it makes you a higher risk anyway.  Then you're paying more money for something that's completely out of your control.

Out of all of these ideas, there's one thought that remains prevalent in my mind.  One question has bothered me for years and makes me wonder when consumers are going to start going on the offensive:

At what point does risk-assessment become discrimination?

I have no doubt that eventually this topic should come up.  One day we'll see someone taking an insurance company to court for charging them rates they can't afford based on a situation that they can't control.  I'm sure it's already happened somewhere that I haven't heard of, and maybe they got a settlement or the whole situation dissipated while being ignored by the media, or (the more likely scenario) the customer simply couldn't afford a lawyer and soon faded into quiet poverty.  And yet, despite the unfairness of many of the things they do, insurance companies can point at the math and get out of any conflict.

Statistics prove that a certain type of person will cost more to take care of.  But individual situations?  They can never be predicted.

Saying that a man should pay more for car insurance is essentially saying that you assume he's going to wreck just because he's a man.  Jacking up rates for a woman with a heart defect is making her situation just as unfair as discriminating against someone with a handicap.  

And employers bound under discrimination laws?  They could easily prove with statistics that an older employee is a higher risk because they have more injuries in the workplace, or that a female shouldn't take a hard-labor job because she would present a higher risk to them if her statistically weaker muscles were to give out.  And yet we don't allow them to refuse hiring a person based on age or sex.

Insurance companies aren't held to the same standards as employers are.  Where should we draw the line?