id venture anything under $200/oz USD is fake. it is generally sourced as a byproduct of the petrochemical industry.
As for different things, about 7 years ago in LA there was as huge wine counterfeit operation bust. Expensive bottles were filled with cheaper wine, re-corked and sold. This is why expensive bottles now "destroyed" one way or another.
Point is - easier to sell and fewer troubles.
Real 100 year old Balsamic vinegar is $200/oz though: https://giusti.com/products/giusti-100-reserve