Is a comment between the function parenthseses and curly brackets considered a bad practice?

Given a file like this:

#!/usr/bin/env bash
foo() # subject
{
    :
}

The curly brackets are red in VIM 7.3. If I remove the comment on the second line, the curly brackets change to turquoise. Is this intentional - some sort of warning of bad style?

I'm pretty sure the two are be semantically equivalent.