In the last 2 years all disciplinary actions have been against non-FRA members.
There is also some evidence (though where it is I am not too sure) that membership of an organisation results in greater adherence/awareness of the rules. Obviously being an FRA member doesn't automatically make you someone worth trusting on the fells - some FRA members I know I definitely wouldn't trust!
I stated these two points in my earlier tl:dr post.
Stricter enforcement is in place at some races (see for example Edale Skyline for kit; Trigger for pre-race vetting) and maybe these incidences of best practise could be spread further. However there's always people intent that they know best (e.g. I believe an experienced Spine racer was DQ'd this year)
Personally? For a smallish evening race I wouldn't alter entry fees. If I organised a Lakeland Classic or the two races organised above, that are more arduous, have become more 'bucket list' type events or are well subscribed, I would. I think there's more room for nuance here than there is in the GPS debate.