People who eat broccoli (along with other vegetables) as part of a healthy diet are less likely to be obese or have weight related illnesses.
In order to promote a healthy society, the federal government should be allowed to mandate the purchase of broccoli (and other vegetables).
Does that sound right to you? If not, you are against the Affordable Care Act - because it is effectively the same thing. In fact, Justice Ginsburg used a similar argument to state her case for upholding the ACA when it was under review.
If that sounds ok, then I have another scenario for you:
Congress passes a law. They use a few parliamentary tricks to force it through, but at the end of the day it does pass.
The Supreme Court upholds the law, but only after they change a fundamental part of it - making it no longer the same law that Congress passed.
After the law leaves the Supreme Court, the President takes his red pen to it. He arbitrarily changes a few provisions, adjusts whom the law will affect, and exempts some of his friends from following the law at all.
Do you have a problem with that?
If so, you just sided with the House Republicans.* Yeah, I said it. It is both their prerogative and their responsibility to prevent the President from unilaterally changing and unequally applying the law - even if you agree that it is the settled law of the land. Not that this should be a party issue at all at this point - Stopping further implementation of what amounts to a redistributive tax thinly veiled as "health insurance" should simply be about equal treatment and fairness. And this law, as it is currently being perverted and applied is (if possible) more unequal and more unfair than it was when it was written.
*Also, I'd like to clear up a little misconception: the Republicans did not decide to shut down the government. No one decided to shut down the government. There was no vote to shut down the government. What Republicans did was fund the entire government except for the ACA. The Senate voted down said funding - at least four times - and the President promised to veto those funding measures if they made it through the Senate.