It would be great if, in addition to -X, --exclude-type=TYPE, there was a --include-type option....
If include-type is given (first) then per default no fs type shall be included but the ones given there.
i've wrote a patch for that issue and opened a PullRequest for it on Github.
Here's the link: https://github.com/nagios-plugins/nagios-plugins/pull/44
A patch that adds such an option has been applied.