I can't find hash rate numbers for ZEIT, but given that its total market capitalization is ~ 18 bitcoins and that it uses Scrypt for POW, it's obviously incredibly easy to attack. There is no comparison.
Miners don't attack ZEIT because it's worthless. That doesn't mean it's secure.
Hey, let him buy that country estate with his, er, Zeit?
That's if he can get more than $5 out of the market before killing it stone dead.
I then look forward to him boasting about it on here so I can double spend the transaction using my Casio electronic organ. It's got a drum pad too.