This specific directive actually makes sure that EU's bank shareholders and creditors take the first hit in the case of a bank collapse. Then people with over 100,000 euro in their accounts will be hit, but is stated that depositors lower than 100,000 euro won't be affected. I'm not saying that the government or banks should ever be able to take your money like this. But it is very similar to the US FDIC of $250,000. Basically your money is only safe in banks if it is less than $250,000, if you have more cash in a bank than that and the bank goes under so does all of your funds over that $250,000 mark.
The EU directive for bail-ins and the deposit insurance are two separate things. The deposit insurance in case of a BANKRUPTCY of a financial institution in the EU is similar to the FDIC in the US and is already in place (100,000 Euro coverage). In contrast, the "bail-in directive" is a measure in which the share holders, bond holders and the deposits over 100,000 take a hit in order to PREVENT a BANKRUPTCY of the bank. In other words, a bankruptcy of a bank is impossible, because the owners and customers can be forced to bail out the bank before it is going to get into trouble.