Because they are passing the cost of the insurance on to the employee. The employer isn't paying you less because you have a family, just charging you more beca

Because they are passing the cost of the insurance on to the employee. The employer isn't paying you less because you have a family, just charging you more because it costs more. Health insurance offered through your employer also costs more the older you get, but an employer can't just decided to pay you 10% less when you hit 50. Age is a protected class, but that has no impact on what an employer charges for health insurance.