That’s against regulations if you live in a unit price mandated state. You can report misuse of unit price labeling to your State Director.
According to NIST SP 1181, under Consistency of Units and Measure:
The declaration of the unit price of a particular category of product in all package sizes offered for sale in a retail establishment shall be uniformly and consistently expressed in the same unit of measure. The same unit of measure should be used whether a product category is sold in a fixed weight pre-pack, loose from bulk, or in a random weight pack.