Actually, I’ve found plastic food containers/pitchers that were made in the US at a Dollar General, and haven’t seen that anywhere else.
Dollar Tree is good for one or two of the smaller American soap manufacturers (7 oz bars without cheap terrible ingredients).
You certainly do have to read the labels, but the dollar stores stock smaller manufacturers and unlike the bigger brands, some of these are still US made.
I agree with your observations about the smaller brands, like jellies and candies.