You laid out the exact reasons I stayed as long as I did at my last job, even after it became clear I was not happy with my compensation. (except for the moving part - hurray living in a 'tech' town with lots of opportunities I guess.) Although I am really confident at this stage of my career in my abilities and reputation, interviewing is such a pain in the ass overcoming that inertia takes a bit, and you are right, companies count on that inertia.