Technically, yes. But, it would have picked up all the stuff from your stew, so if you were to then put it in a cream sauce the cream sauce would then taste all stewy. And really, they aren’t that expensive, and it’s kinda gross. You’re kinda getting into a really gross area, like when people buy sheets or underwear used. If you’re really that hard up for spices, you can go to Whole Foods or other health food stores and buy them from the bulk foods section for shockingly cheap. Most of what you’re paying for in a supermarket is the nice little container, anyway.