question about file mask options that claim to not allow pathnames

The doc says that certaion dar options take a file mask, which the doc
claims is not a path.  However, some examples in the doc of file
masks are like --exclude-delta-sig "home/joe/*", which suggests that the
mask is not just for the filename, but can apply to the path as well.
What is the usage distinction between an option that applies a mask on
a path vs. one that applies it only to a file?  Is the distinction
about whether or not the --fs-root is included?