Mine had, among other things, a couple boats, a camper, and a giant pile of lumber on it. This one seems to be mostly containers.
My guess is this: Gas doesn't go on sale. It doesn't have to. There are two places in town to buy it, and it's the same price at both. I'm guessing that the tanker is here to fill up the storage tanks, and they realized there was too much gas in them from last winter, so they're trying to sell off the old stuff before they fill up the tanks with the new stuff. But that's just a guess.
This guy has been sitting out on the horizon for several days. It must be frustrating for the men on the boat to know that they're this close to restaurants, pretty girls, and beds that don't rock, and still not be able to come in.