Why would a company make health insurance mandatory?

I am one of the rare people. I am young, healthy, and pay for my own Dr. visits. I am pissed off by the line "You must select one coverage plan or show proof of other insurance." Why must I show proof of another plan? I am a responsible person. Yes, I know emergencies do occur, but this question is not about that. I feel that I am paying other's people's bills by even contributing to such a plan. I clearly don't use my share.
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You are, in fact, helping to offset the unhealthy, older employees costs by getting on the group. If they let you get your own policy, that is probably a less expensive option. A high deductible plan would save you money over a "bells-and-whistles" PPO or HMO and still let you mitigate those larger risks.
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