Well, yeah, exactly, but that's why it's the law. Stealing is a competitive advantage (for the thief), but a net negative for the society, which is why it's illegal and persecuted.

I agree with you, that the law should be as small as possible, but you're missing the second part (just as important IMO) - that the law (small as it should be) be enforced fully and applied fairly.

If she doesn't say no it's a competitive advantage to other suitors, right?

That's literally what you're advocating for.