That does seem high. Here’s the website I used to grab the average: Maine Heating Fuel Prices

I’d check with them, ask them why they are nearly double the average. Was it an emergency delivery? Off hours?

Or may be dependent on how much you use, or don’t use: “Households using propane just for cooking or hot water generally pay a higher per gallon price.”

They would/should have left a receipt showing how much they put in. Or call them and ask. How big are your tanks? Average price for propane in Maine is around $3.25/gallon. So them adding 30-ish gallons to each tank seems normal to me. I have 2ea. 120 gallon tanks which I let run pretty low and just spent $600 filling up last week.