Recently a man was deceived by someone who had change the electrum source code on an old version of it. He lost 1400BTC(!)
I had made a similar question in the past, but the answer didn't satisfy me. Why should that hacker use a mixer? If he try to sell the bitcoins from his main address (the one with the 1400BTC) he will get caught, because he will prove that he is the hacker.
If he send 1BTC to 1400 owned addresses, though, no one can prove that the person that owns those 1400 addresses is the hacker, right? They can only ask them where did you get that one bitcoin.
Look deeper - no one will ask where a person got this bitcoin, since all bitcoin transactions are transparent and you can see who sent it to whom and when. All these wallets that will contain one bitcoin will eventually lead to one wallet and this will cause a huge number of questions. In any case, all transactions are transparent and you need to keep this in mind.