Not sure if this counts, but there's something I noticed about the show.
The technology that the citizens of Bikini Bottom is generally a couple decades behind what ours is like. Look at their phones. And even the younger characters on the show are in possession of record players, as opposed to something more modern. That was probably intentional on the artist's part so the show would always be "classic" and timeless, or maybe it was done to signify that the show takes place in a world that's different from ours. Or maybe it was just an aesthetic/stylistic choice.
Their technology and a lot of their things might be collected/salvaged from shipwrecks or just from incidences of objects falling off of boats (in the case of Spongebob's house, and the magic pencil.) The Krusty Krab is fashioned from an old lobster trap (and its trapping abilities seem to have been re-purposed as extreme security methods,) and the fancy restaurant from "Krusty Love" is a large bottle.