I know the answer you will hear from Hugh - and it's an inconvenient truth.
Unfortunately the Fabrik element plugins weren't all written and created with the Fabrik 'big picture' in mind. Most were submitted from other projects by various contributors. And it would be a major undertaking to get them all working so as to all behave the same and all play 100% by the same rules, with the same features (like 'hidden'). That's why some have that option and some don't. Maybe someday - but for now, it is what it is.
Unfortunately the Fabrik element plugins weren't all written and created with the Fabrik 'big picture' in mind. Most were submitted from other projects by various contributors. And it would be a major undertaking to get them all working so as to all behave the same and all play 100% by the same rules, with the same features (like 'hidden'). That's why some have that option and some don't. Maybe someday - but for now, it is what it is.