Every boat owner encounters that! I had a 40 ft cruiser with twin 140 gallon gas tanks..... we take some non boating neighbors out... and they insist to pay for gas. I pull up to the marina and start filling both port and starboard tanks, each had about 1/4 tank, gas was $5.15 a gallon ( 5-6 years ago).
I stopped at about $450 bucks... He gulped and broke out in a sweat....!
I told him it was my treat... we had a great evening cruise!
They did bring some great craft beers and wine for the wife.
But what a priceless look on his face!
a full day out on lanier on a 40 foot cruiser is easily worth 200 - 300 bucks!