Should employers be able to make overweight workers pay more for their health insurance?

...because it is costing more to insure them. Do you also support/not support charging more for smokers? Are there any other groups who should be paying more?
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At a previous job of mine, I had a pretty good health plan. The employer was putting in well over $10,000 a year. I haven't even been to a doctor for so much as a routine checkup in well over 4 years. I opted into the health insurance because my share of it was pretty cheap, and I figured I might need it if I broke a leg snowboarding or something like that. I never got anything out of that $10,000 a year my employer put into my healthcare - and they could have just cut me a discount, and paid me the extra cash as a bonus of something - but it wouldn't have been legal for them to do this. It seems like I was kind of getting the short end of the stick, having my employer spend $10,000 a year on a healthcare plan that I never even used. Meanwhile, my coworkers who ate junk food all the time were in effect getting paid $20,000 a year more than I was because they were getting their money's worth out of the health care plan, and then some. I'm not sure exactly what my current employer is spending on my healthcare but I don't imagine its much cheaper. I believe there ought to be some sort of rebate system or other incentive for people who eat a healthy diet and choose not to bring sickness and disease upon themselves with unintelligent nutritional choices.
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