That’s not the only issue. Some flash drives have been found to completely misrepresent their sizes. There was something of an epidemic of them a few years ago, so much so that people started testing their drives after purchase (with tools eg Fight Flash Fraud). You could fill up the drive, then it would just completely fail as it did not actually have the storage capacity advertised.

Suffice it to say, the data storage industry isn’t without its own brand of shady practices.