Our boating and fishing are truly precious times for us. We'd rather eat out less, go to a few less movies, have shorter vacations, etc and still enjoy our 2-3-4 trips each summer over to the Bahamas. Look at where you spend all of your discretionary income and maybe there are places where you can cut back there so that you can still enjoy being out on the water.
One way that I constantly save .25-.60 a gallon on my fill ups (of 200-250 gallons!) is by having it delivered to the house where we have the boat. The company that I use down in South Florida has a 100 gallon minimum, but a simple phone call is all the "work" that I do to fill up my Marlin! A CC # on file takes care of the payment. For me to run down to the local fuel dock to fill up (at a higher price!) will burn 5-6 gallons, so it costs me $20-25 to go get filled up before the big trips!
Do some research in your local areas for fuel companies that deliver right to the boat. For you smaller boat guys, see if they will fill up two boats at the same location to get you above the minimum amount. Have your buddy or neighbor swing by your house for the twin fill ups.
Go through your boat and take off all that "stuff" that you carry around and probably don't need on every trip. Weight burns fuel to carry around. I'm guilty of that as I leave a spare anchor with 300' of rode as well as a heavy 50' shore power cord aboard when I really only need that aboard on Bahamas trips.
For local trips, so you really need full tanks? I'm no longer filling back up with 225-250 gallons after my last Bahamas trip of each summer because I only need 100-150 aboard to do local trips, cruises, etc. This also keeps me putting fresh gas in the tanks over the Fall, Winter and Spring......
Slow down my boating because of $4.25 a gallon gas? If I did that this summer, I'd probably regret it next summer when $4.25 might seem like a real bargain!
Fish On!