A lot of stuff does have interstate implications. Especially now that most corporations operate in an interstate fashion.

That said, I agree that it's overused. I personally think that the 9th amendment should be used in a lot of cases, like civil rights, instead of the interstate commerce law.

The supreme court, however, has basically decided that the 9th amendment doesn't really exist.

You could just as easily stuff most of those things under the "general welfare" clause if you do the same rigamarole of years and years of precedent hand-waving. We live in a post constitutional state. The constitution is just something worked to backwards so the guys who function as our priests/gods point to the document because that's the only way to feign some sort of legitimacy to our government.

Ultimately none of us signed the constitution and all of those people that did are dead. It is a religious artifact used by the whig -god people to argue they are right. Not something followed with faith to the historical context nor literal contract.

(edit: to below trying to compare bad-faith ICC to good-faith general welfare, you must apply similar levels of creativity and bad faith. Ban things through high or impossible to pay taxation. "Tax" behavior to force people to do something in a certain way, make very heavy penalties for not paying the tax, and also make it extremely difficult to buy the tax stamps (this is how they did drug control until they decided to use the new fraud of "interstate" commerce).