So you do have a discretion on what kinds of dependency qualify as selfishness or greedy? Assuming that, even your question was a whole different can of worms as well, that you find it unjust that minors pay tax? Just assuming that of course.
You're habit of framing this as an issue of "taking without paying", iow being dependent on others, is irrational and unsupported by the facts of how universal health care actually works.
Here is how it actually works:
1. We all pay for the services.
2. We all use the services.
3. We are not charged at the point of services.
Since nobody in Canada is forced to deal with private insurance companies or shoulder
enormous amounts of debt to pay for health services, we are MORE free and independent than Americans, at least when it comes to health care. We are not dependent on the profit margins and quotas of private health insurance companies.
I know you're feeling pretty proud of yourself, having your first job and making a bit of money. That's good and admirable, and it feels great to be financially independent. But under your health care system, one serious injury or illness could put an end to all that. However much you're earning, it's not enough to pay for cancer treatment or a heart transplant, and in all likelihood it will NEVER be enough.
When you are not on your parents' plan any more and have to buy your own health insurance, I think you are in for a shock. Some folks here are paying hundreds or even thousands of dollars a month. Are you earning enough to cover that kind of expense?
We don't pay that fee in Canada. At all. Ever. We have more money in our pockets that we can use for things that are genuine symbols of independence, like property, travel, vehicles, etc.