Here are some things that came to my mind.
I've never heard of gas coming [pre Stablized] How much Stabil do you add per 10gal? [I do 1oz Stabil to 10gal]
That's Crazy on changing your Racor filter every 20hrs..... I change it once a year and we average 100hrs a year.
Now..... I would agree that the fuel your buying may be dirty.....or coming from a dirty tank.
So here's your fix on that.
https://www.amazon.com/Mr-Funnel-AF3CB- ... B000SOIRCG
Yes it will be a lot more hands on and a PITA due to it being slower to fuel the boat.... But these things Work.
And you will be able to have show & tell with your marina if they are pumping dirty fuel.