Recently, many Bitcoin Holders 
have been the target of criminal gangs who abduct and force them to move their huge investments in BTC and or Ether into the personal wallets they control. This is very common with Bitcoin Hodlers and also ethereum. We all know that to move all your BTC or ETH to another wallet is just a click away as such, this makes it very lucrative for criminals than forcing victims to make bank transfers.
Interestingly, in an article By Nathaniel Popperfeb posted in New York Times on Feb 18, 2018, titled "Bitcoin Thieves Threaten Real Violence for Virtual Currencies"