Check this out guys, apparently you don't have to pay entry fees to the Exmouth National Park if you show your rec fishing license and say you are entering specifically for the purpose of fishing, this is what the website says:

http://www.dec.wa.gov.au/campgrounds/index.php?option=com_jomres&Itemid=2&task=viewproperty&property_uid=106

• Seniors' Card, Age Pension, Disability Support, Disability Support (Blind), Carer Payment, Carer Allowance, Department of Veterans' Affairs (DVA), Companion Card

The accompanying companion/carer of a Companion Card holder is entitled to free entry when entering an attraction or venue where 'per person' fees apply. This also applies to camping fees.

Community groups travelling on buses may be entitled to a reduction in fees so check with the local DEC office before you visit.

Holders of Recreation Fishing licences may enter a park at no charge if they are entering for the purpose of their licence - licence to be shown on request."

Cheers,

Adam

I have followed this up:

For those persons that hold a current fishing licence, whether it be boat fishing, rock lobster, netting etc. and enter the park for the sole purpose of carrying out that fishing activity they are entitled to free entry.  However if they camp then they have to pay camping fees and if they do any other activity in the park then they have to pay entry fees.