I don't know for the US, but in Europe fake honey is a big problem. There were several grocery chains who had to call back their honey because of it
Yes. Good episode about fake honey and its interaction with almond growing: https://freakonomics.com/podcast/beeconomics-101/
That has been a global problem, lots of it in the US as well. I tend to only buy honey from known local producers, either at specialty stores or street markets.
Fun fact: The crime of passing off inferior sweeteners as (higher-priced) honey is referred to as "honey laundering".
https://kinghavenfarms.com/blogs/from-the-hive/the-sticky-bu...