I don't agree. Stealing money from thiefs is still stealing.

Any scammer/hacker will always find someone to exchange his altcoins or BTC into Monero ; or will always find a place to mix his coins if needed. This fight is lost in advance.

If, for example, scammers bother you, the only way to combat them is to educate users -as much as possible- so that they don't get scammed. Treating the consequences but not the roots is useless.