Something you buy that's cheap or badly made is dreck. While you can find great bargains at a dollar store, most of what they sell is dreck.
Use the word dreck when you're talking about products that are worthless, flimsy, or of poor quality. Terrible art and trashy shows on TV are also dreck, as is a badly written book or a political speech that's full of lies and exaggeration. What these things have in common is a lack of value or quality. Dreck is a Yiddish word that comes from the German Dreck, which means both "dirt" and "manure."