If the game freezes, just click inside it (games can get unresponsive if you click elsewhere on the page).
Despite the trope's prevalence in fiction, historical pirates weren't much for burying treasure. Each day takes you to a different islet with numerous buried treasures and one "secret" treasure hidden therein. Click on a square to move to it, and click on the square you're standing on to dig for (hopefully) treasure. Analysis: The theme was "sandbox", and the game does successfully capture the feeling of two kids playing as pirates, digging up treasure in the backyard. There's some kind of visceral joy about uncovering something in the sand (an interesting shell, a piece of sea glass, a mysterious old coin...) and Cap'n GoldGrubber excels at replicating that experience. A large part of the game's appeal is the titular captain. Kudos to Joshua Tomar for his exceptional voice acting. It's fun to hunt treasure (though occasionally made difficult by the scenery), but, once you've purchased a handful of upgrades, finding becomes so easy that it becomes non-challenging and repetitive.
This game is played with mouse only.