[eesmith]

Why do people keep making this claim?

There are plenty of laws which don't have an implicit threat of prison behind it.

Here's one: https://www.law.cornell.edu/uscode/text/4/1 . Quoting Wikipedia: "This is a U.S. federal law, but only suggests voluntary customs for handling of the American flag and was never intended to be enforceable. The code uses non-binding language like "should" and "custom" throughout and does not prescribe any penalties for failure to follow the guidelines." - https://en.wikipedia.org/wiki/United_States_Flag_Code

[macspoofing]

You're really stretching.

[eesmith]

I honestly don't know why I'm so downvoted.

There are laws naming post offices and other objects. There are law recognizing people and bestowing honors on them. There are laws which cancel previous laws.

There are plenty of laws which have no threat of punishment.

But I'll set that objection aside.

Let's go back to CJefferson's comment, to be more concrete. "inheritance should not be a right, when the original money was acquired illegally."

Money (at least as CJefferson refers to) exists because of laws, and the way we think of money exists because of laws. Inheritance is a legal concept, enforced by laws. So the right to inherit millions of dollars by your definition exists because of the implicit threat of prison.

Thus, changing the law as CJefferson describes doesn't necessarily add a new threat of violence - it could change the balance of the existing threat of violence, or even reduce it.

Thus, an argument against changing the law simply because laws carry a threat of punishment is really an argument to maintain the status quo for the existing threats of violence. It is not a strong argument against changing the law, which is what I think you meant it as.