Because it would make the show unstable. Besides Squidward gets tortured so much these days that the blasted new writers are very unlikely gonna adjust some good changes to Squidward with him living, in like, say, a new location in Bikini Bottom or on Flying Dutchman's ship. The Flying Dutchman also hates Squidward by the way so that makes even less sense.
Besides Squidward already moved away in two episodes, Squidville and New Digs. Squidville involved Squidward living among his own kind and he was finally happy, but he ended up acting like SpongeBob (which is fun crazy) at the end. And in New Digs it ends with the episode Squidward trying to live at the Krusty Krab instead of SpongeBob.