The problem isn't necessarily hoarding but rather governments decided to only have one legal tender and sabotaging that legal tender is effectively the same as sabotaging the entire economy. Hoarding is a kind of sabotage but if people hoard something that isn't legal tender they are not threatening the economy.

The wealthy might be hoarding Lamborghini's but we can always build more cars. Can't do that with money unless the government or a commercial bank does it.