$30,000 coin

Saw this coin today worth more than a nice car. 
 

Can anyone explain this to me

Sorry for the bad picture 

There are coins that go for nice mansion money. Like everything somebody wants something and someone else sells it because it is rare and/or popular for the highest amount they buyer will tolerate.

https://www.ngccoin.com/price-guide/world/iles-de-france-et-bonapart-10-livres-km-1-1810-cuid-1174205-duid-1506631

According to NGC, high-condition examples of the Iles de France 10 livres that are well struck go for a large premium. Apparently, the finest known example went for $33,000. Provided this coin is an MS-65 holder, it appears to be a fair deal. As far as counterfeiting goes, it doesn't look like the kind of coin counterfeiters would go for if they wanted to sell replicas or fake coins.