Well, what do we expect? They are addicts. But indeed that optimism seems not a right word to use there, since there is no point on why they continue doing it. They are like a cool guy when they say that being addicted is only just a minor thing for them. But for us, even a small loss is already a big deal. They look so confident when they say that, but deep inside there must also be a despair, regret and other negativities that they can feel.
We shouldn't blame or hate them but instead, we can do much better like trying to talk to them seriously about their problem. Once they get comfortable. That's the time they can confess and start trying to change their lives.