dont know how can you protect yourself, but by submitting ticket you can get back everything... almost everything back. Only pets can't be restored back.
Yeah right...submited a ticket 2 weeks ago...still waiting. Guess i should have sent my bank account number on it.
My account was hacked too - 1st time of my many years of playing L2. But in my case they answered in few days (max 7days) and restored all stolen items, except fenrir.
Dont' know if it have any connection with new trade bot via browser but it was few days after i've used it...
PS. and yeah they like money:D but who's not?
But looking at the reason of ban my friend account ("stealing" items from shared account) it looks like they like more money than players:)