This is such a weird comment to make: these are companies that can quite literally (and quite often) let you go for any reason at all (if you live in an at-will-employment state). I've done this exact thing before, and I've also resigned without 2 weeks notice to chase greener pastures. Business decisions should always be purely transactional and borne out of your own interest. Anything else is self-sabotage.

Companies sure as shit don't care about you, and you caring about them gives them a leg up, not you.