Not sure if this is exactly what you're thinking of smyith, but there is an obscure PDGA format where no player (member or not) pays the $10 non-member fee...it's called a Competition Endowment Program Charity Event.
Endowment program is a great way to raise a little money and potentially attract a few non-PDGA members to a slightly more "casual" C-tier type tournament, but still a PDGA where you can compete and learn to utilize the proper rules too.
A great recurring one coming up in a few weeks in Raleigh too, Jan. 18th... Raleigh Winter Jam. Great TD, tournament runs smooth as butter, good payout, good chunk of change given to local charity. Fun course too, old school but still a great challenge and worthy of a PDGA.
Always freeze my duff off though.